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A352347
Least odd prime p such that q divides 2^p - p^2, where q is n-th prime of the form 8*k +- 1, or -1 if no such prime exists.
1
5, 31, 29, 89, 11, 11, 13, 89, 7, 283, 29, 211, 13, 643, 2711, 491, 1627, 1699, 283, 727, 1493, 1663, 37, 89, 907, 1039, 73, 571, 2707, 149, 179, 197, 443, 463, 1187, 4133, 383, 359, 251, 1567, 4603, 3469, 2069, 313, 677, 1319, 2441, 647, 3733, 3623, 31, 1447
OFFSET
1,1
COMMENTS
Inspired by A350964.
In the first 100000 terms, greatest prime encountered was 204114067.
Records: 5, 31, 89, 283, 643, 2711, 4133, 4603, 8317, 23561, 25819, 45083, ...
LINKS
EXAMPLE
a(1) = 5 since A001132(1) | 2^5 - 5^2 = 32 - 25 = 7.
PROG
(PARI) f(q) = forprime(p=5, oo, if(Mod(2, q)^p == Mod(p, q)^2, return(p)));
lista(nn) = forprime(q=7, nn, if((q+2)%8<4, print1(f(q), ", "))); \\ Jinyuan Wang, Jul 14 2022
CROSSREFS
Sequence in context: A255677 A256153 A238196 * A172030 A042837 A354881
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Mar 14 2022
EXTENSIONS
Name edited by Jinyuan Wang, Jul 14 2022
STATUS
approved