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A091632
Excess of n + product of digits over next prime associated with A091628.
5
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
1,2
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.
LINKS
Carlos Rivera's Prime Puzzles and Problems Connection, Puzzle 251, Pointer primes
FORMULA
a(n) = A091630(n) - A091631(n).
EXAMPLE
a(2) = 235 - 227 = 8.
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Enoch Haga, Jan 24 2004
EXTENSIONS
Edited and extended by Ray Chandler, Feb 07 2004
STATUS
approved