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A188133 Primes p such that 10p+1 divides 2^p-1. 1
43, 487, 547, 571, 883, 1459, 1663, 1723, 2539, 3319, 3511, 4903, 5107, 5431, 6199, 6367, 8011, 8599, 9007, 9391, 9511, 10111, 11119, 11959, 12379, 12703, 13291, 13339, 13999, 14083, 14551, 14767, 15187, 15319, 15859, 15991, 16183, 16603, 16747, 17659, 18427, 19699 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

It is known that divisors of M(p)=2^p-1 are of the form 2kp+1. For k=1, these are the Lucasian primes A002515, for k=2 there are no such divisors, for k=3 these divisors are listed in A188130 and for k=4 in A122095.

The equivalent sequence of prime indices is 14, 93, 101, 105, 153, 232, 261, 269,....

LINKS

Table of n, a(n) for n=1..42.

FORMULA

{p = A000040(i): 10*p+1 | A001348(i)} . - R. J. Mathar, Mar 21 2011

PROG

(PARI) forprime(p=1, 1e5, Mod(2, p*10+1)^p-1 | print1(p", "))

CROSSREFS

Sequence in context: A247966 A248206 A140849 * A194784 A184153 A184145

Adjacent sequences:  A188130 A188131 A188132 * A188134 A188135 A188136

KEYWORD

nonn

AUTHOR

M. F. Hasler, Mar 21 2011

STATUS

approved

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Last modified March 22 04:32 EDT 2019. Contains 321406 sequences. (Running on oeis4.)