"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.’ "