Frank frowned, thinking. Why had the aliens shut up? They’d replied exactly as the aliens had, showing that humans understood prime numbers, and—
No. All they’d shown is that humans can parrot things back at them. “Try continuing the sequence,” said Frank.
Clete nodded, immediately seeing it as well. “They gave us the first five primes; give ’em the next five.”
The captain nodded and lifted a small intercom handset off the wall, pulling it close to him. “Signaling room—continue the sequence. Give them the next five prime numbers.”
“Sir, yes sir,” said a staticky voice, “but, ah, sir, what are the next five?”
The captain looked at Frank, eyebrows lifted. Frank made a disgusted frown. Clete rolled his eyes. “Eleven, thirteen, seventeen, nineteen, and twenty-three,” Frank said.
The captain repeated the numbers into the microphone. “Sir, yes sir,” said the seaman’s voice.
“We better get up there,” said Clete.
Frank nodded. “How do we get from here to where the controls for the searchlight are?”
“Come with me,” said the captain. He led them to a circular metal stairwell and took them up to the radio room. As they entered, Frank saw the seaman who had been operating the light. He was a young white fellow, maybe nineteen, with a half centimeter of blond hair. “The aliens have started flashing again,” he said.
“What was the sequence?” said Clete.
“They repeated back all ten prime numbers,” the seaman said.
A wide grin spread across Frank’s face. “Contact.”
The captain was looking out the window. “The Russian sub is signaling the ten numbers, too.”
Frank pointed. “And here comes that damned cruise ship.”
The yellow beacon started flashing again. One. Four. Nine. And then so many flashes that Frank lost track.
“It’s gotta be squares,” said Clete. “One squared; two squared; three squared; four squared.”
“Give them five-squared as a response,” said Frank, looking at the young fellow. “That’s twenty-five.”
The seaman started clicking the trigger button for the searchlight as he counted out loud.
“God,” said Clete, pointing out the window. “God.”
The alien craft was lifting out of the ocean. It rose about twenty meters above the waves, water streaming off it. Its hull had stopped changing colors; it was now a uniform dark green. There seemed to be four jets of some sort positioned on its underbelly. They churned up the ocean surface beneath. The ship started moving slowly horizontally. It flew in the direction of the Russian submarine, but stopped just short of the vessel, apparently to prevent its jet exhaust from blasting down on the sub. The lander then flew over to near the cruise ship. With binoculars, Frank could see people on its deck taking photographs and home videos. Then the spaceship changed direction and headed toward the Kitty Hawk. It stopped about five meters off the projecting bow of the flight deck, and just hovered there.
“What’s it doing?” shouted Frank.
Clete shrugged.
But the seaman spoke up. “Sir, I believe it’s waiting for permission to land, sir.”
Frank looked at the young man. Perhaps he’d dismissed him too quickly.
“I believe the boy is right, Frankie,” said Clete. “They know this is an aircraft carrier. They’ve seen our helicopter take off and land from it, and they can probably tell just by looking at the planes out on the flight deck what they are—they’re clearly designed according to aerodynamic principles.”
“By all means they can land,” said Frank. “But how do we tell them that?”
“Well, if the question is obvious, the answer must be, too,” said Clete. “Give ’em the prime numbers again. Do it correctly, and that’s ‘yes.’ Do it incorrectly—say, one, two, three, five, eight—and that’s ‘no.’ ”
Frank nodded. “Signal the first five primes,” he said.
The seaman looked at his captain for confirmation. The captain nodded, and the seaman used his thumb to operate the light trigger. In the window, Frank could see the alien ship moving over the flight deck.
The intercom whistled. The captain picked up the hand unit. “Raintree here.”
“Sir,” said a husky voice, “the Russian sub has radioed us, asking that we send a helicopter to bring three observers over here immediately, sir.”
The captain looked at Frank, who frowned. “Christ, I don’t want—”
Clete interrupted. “Now, Frankie, they chose international waters. You can’t really—”
“No, no, I suppose not. Okay, Captain.”
“Take care of it, Mr. Coltrane,” said the captain, and he replaced the hand unit in its clip.
“I want video equipment set up on the flight deck,” said Frank. “I want everything recorded.”
The captain nodded, and spoke into the intercom again.
“Let’s get down there,” said Clete.
Captain Raintree, Frank, and Clete went back down the circular staircase they’d gone up earlier, and emerged from the same door at the base of the conning tower, exiting onto the flight deck. There wasn’t much wind, and the sky was mostly clear. The lander was still in the process of lowering itself.
“Damn,” said the captain.
“What’s wrong?” asked Frank, over the roar of the lander’s exhaust.
“It’s setting down in the middle of the runway. No way we can launch a fighter with it there.”
Frank shrugged. “It’s the biggest clear area.”
In the distance, another Navy Seahawk was now hovering over the conning tower of the Russian sub. A rope ladder had been lowered, and a man was climbing up into the chopper.
Captain Raintree looked at Frank. “We do have recorded music, sir. We could play the national anthem.”
“Is there a United Nations anthem?” asked Frank.
“Not as far as I know, sir,” said the captain.
“Anybody got the theme from Star Trek on tape?” said Clete.
The captain looked at him.
Clete shrugged. “Just a thought.”
“I could assemble an honor guard,” said the captain.
“With rifles?” said Frank. “Not on your life.”
The lander came to rest. Frank could feel vibration in the deck plates beneath his feet as it clanged against them.
“Shall we go have a look?” said Clete.
“Sir,” said the captain, “the lander could be radioactive. I suggest you let one of my people check it over with a Geiger counter first.”
Frank nodded. The captain used the intercom again to give the order.
“Do you suppose they’re going to come outside?” asked Clete.
Frank lifted his shoulders. “I don’t know. They may be incapable of coming outside—even if they have space suits, the gravity may be too high for them to move around.”
“Then why land on the Kitty Hawk at all?”
“Maybe they were just getting seasick being tossed on the ocean.”
The helicopter was now leaving the Russian sub and heading back toward the Kitty Hawk.
Clete pointed at the gray-green markings on the ship’s dark green hull. They were complex, consisting of a horizontal line with various spirals and curves descending from it. No way to tell if the whole thing was one character, or if it was meant to be a word, or just abstract art.
A sailor appeared next to the captain, holding a Geiger counter. The captain nodded for him to proceed. The man looked nervous, but headed out across the flight deck toward the lander.
“Captain,” said Frank, “can you sail this ship to New York?”
“Want to take ’em to see Cats?” said Clete.
Frank frowned. “To the United Nations, of course.”