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A092224
Numbers k such that the numerator of Bernoulli(2*k) is divisible by 103, the fifth irregular prime.
10
12, 63, 103, 114, 165, 206, 216, 267, 309, 318, 369, 412, 420, 471, 515, 522, 573, 618, 624, 675, 721, 726, 777, 824, 828, 879, 927, 930, 981, 1030, 1032, 1083, 1133, 1134, 1185, 1236, 1287, 1338, 1339, 1389, 1440, 1442, 1491, 1542, 1545, 1593, 1644, 1648
OFFSET
1,1
COMMENTS
103 = A094095(1) is the first irregular prime in A094095. This sequence is the union of 2 arithmetic progressions: (24 + 102*n)/2 and 103*n. Note that the numerator of BernoulliB(2*114) is divisible by the first nontrivial irregular squared prime 103^2, when A090943(1)/2 = a(n) = 114 = (24 + 102*2)/2. Also, the numerator of BernoulliB(2*1236) is divisible by 103^2 because a(n) = 1236 = (24 + 102*24)/2 = 103*24/2. - Alexander Adamchuk, Jul 31 2006
LINKS
Eric Weisstein's World of Mathematics, Bernoulli Number.
MATHEMATICA
Select[ Range[ 1694], Mod[ Numerator[ BernoulliB[2# ]], 103] == 0 &]
Select[Union[Table[2n*103, {n, 1, 100}], Table[24+102*n, {n, 0, 100}]], #<=10000&]/2 (* Alexander Adamchuk, Jul 31 2006 *)
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Feb 25 2004
STATUS
approved