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A218162
a(n) is the smallest positive integer k such that k^16 + 1 == 0 mod p, where p is the n-th prime of the form 1 + 32*b (see A133870(n)).
0
19, 8, 15, 6, 10, 33, 4, 107, 43, 170, 194, 21, 86, 10, 109, 6, 31, 227, 212, 108, 75, 5, 13, 21, 36, 516, 119, 68, 69, 264, 281, 634, 186, 214, 210, 50, 397, 277, 227, 112, 461, 329, 47, 1399, 257, 231, 131, 68, 530, 981, 242, 298, 219, 508, 196, 266, 97, 234
OFFSET
1,1
COMMENTS
A133870(n) : primes of form 32n+1.
EXAMPLE
a(5) = 10 because 10^16+1 = 10000000000000001 = 353 * 449 * 641 * 1409 * 69857 with A133870(5) = 449.
MATHEMATICA
aa = {}; Do[p = Prime[n]; If[Mod[p, 32] == 1, k = 1; While[ ! Mod[k^16 + 1, p] == 0, k++ ]; AppendTo[aa, k]], {n, 300}]; aa
CROSSREFS
Cf. A133870.
Sequence in context: A040346 A364786 A124608 * A064264 A040345 A070685
KEYWORD
nonn
AUTHOR
Michel Lagneau, Oct 22 2012
STATUS
approved