A091632 Excess of n + product of digits over next prime associated with A091628.

0, 8, 10, 42, 72, 176, 354, 764, 1516, 3022, 6066, 12268, 24570, 49148, 98246, 196530, 393158, 786406, 1572834, 3145674, 6291440, 12582874, 25165764, 50331634, 100663192, 201326576, 402653180, 805306350, 1610612690, 3221225038

Offset: 1

Author

Enoch Haga, Jan 24 2004

Keywords

• base
• easy
• nonn

Comments

Sequence arising in Farideh Firoozbakht's solution to Prime Puzzle 251 - 23 is the only pointer prime (A089823) not containing the digit "1".

The monotonically increasing value of successive excess (and product of digits (A091629)) strongly suggests that in successive n the digit 1 must be present.

Examples

			a(2) = 235 - 227 = 8.
		

Links

• Carlos Rivera's Prime Puzzles and Problems Connection, Puzzle 251, Pointer primes

Crossrefs

Cf. A089823, A091628, A091629, A091630, A091631.

Formula

a(n) = A091630(n) - A091631(n).

Extensions

Edited and extended by Ray Chandler, Feb 07 2004