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A114056
Numbers k such that 2^prime(k) - 1 + 10^k is prime.
0
1, 2, 3, 7, 8, 222, 227, 360, 535, 2713, 9079, 22579, 26656
OFFSET
1,2
EXAMPLE
7 is there because the 7th prime is 17 and 2^17-1+10^7 is prime.
MATHEMATICA
Position[PrimeQ[Table[(2^Prime[n] - 1) + 10^n, {n, 10}]], True]
CROSSREFS
Sequence in context: A103173 A098863 A053960 * A168222 A323384 A349641
KEYWORD
nonn,more,changed
AUTHOR
Joao Carlos Leandro da Silva (zxawyh66(AT)yahoo.com), Feb 02 2006
EXTENSIONS
Edited by Don Reble, Jul 23 2006
a(10)-a(11) from Michael S. Branicky, Apr 15 2023
a(12)-a(13) from Michael S. Branicky, Nov 28 2024
STATUS
approved