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A076825
Let u(1)=1, u(n)=2^u(n-1) (mod n), sequence gives values of n such that u(n)=1.
0
3, 15, 21, 51, 65, 95, 165, 255, 261, 273, 285, 295, 345, 387, 465, 507, 513, 565, 641, 837, 1025, 1353, 1665, 1731, 1845, 1953, 1971, 2013, 2123, 2193, 2231, 2325, 2979, 3087, 3237, 3591, 3615, 3645, 3865, 4097, 4369, 4405, 4445, 4655, 4697, 4797, 4995
OFFSET
1,1
FORMULA
Conjecture: a(n)/n^2 -> infinity
CROSSREFS
Sequence in context: A147017 A171570 A350987 * A259745 A118565 A230658
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Nov 24 2002
STATUS
approved