A274003 Primitive terms (not equal twice a smaller term) of A178751: moduli n such that x^y == -1 (mod n) only for x = -1 (mod n).

2, 3, 15, 20, 51, 68, 255, 340, 771, 1028, 3855, 5140, 13107, 17476, 65535, 87380, 196611, 262148, 983055

Offset

1,1

Comments

See A178751 for further information. In particular, A038192 is the subsequence of odd terms.

Links

Table of n, a(n) for n=1..19.

Prog

(PARI) is_A274003(n)={is_A178751(n) && (bittest(n, 0) || !is_A178751(n\2))}
(PARI) select( n -> bittest(n, 0) || !setsearch(A178751, n\2), A178751) \\ assuming the vector A178751 holds enough terms of that sequence.

Crossrefs

Cf. A038192, A178751.

Sequence in context: A173334 A331089 A294131 * A101507 A047176 A347668

Adjacent sequences: A274000 A274001 A274002 * A274004 A274005 A274006

Keyword

nonn,hard,more

Author

M. F. Hasler, Jun 06 2016

Status

approved