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%I #4 Mar 31 2012 13:20:27
%S 2,3,5,7,11,23,47,59,83,107,167,179,227,239,263,347,359,383,443,467,
%T 479,503,563,587,647,659,719,827,839,863,887,983,1019,1187,1223,1259,
%U 1283,1307,1319,1367,1439,1487,1499,1523,1619,1787
%N Prime factor of the distinct numbers appearing as denominators of Bernoulli numbers A090801 that is greater than all previous a(n). a(1) = 2.
%C a(n) is identical to A079148[n] up to a(14)=227. Most a(n) except 2,3,239,443,647,659,827,1223,1259,1499,1787... belong to A005385[n]: Safe primes p: (p-1)/2 is also prime.
%C Except for 2 and 3, the same as A092307. - _T. D. Noe_, Sep 25 2006
%e A090801[n] begins {1, 2, 6, 30, 42, 66, 138, 282, 330, 354, 498, 510, 642, 690, ...} = {1, {2,1}, {2,3}, {2,3,5}, {2,3,7}, {2,3,11}, {2,3,23}, {2,3,47}, {2,3,5,11}, {2,3,59}, {2,3,83}, {2,3,5,17}, {2,3,107}, {2,3,5,23}, ...}.
%e a(1) = 2, a(2) = 3, a(3) = 5, a(4) = 7, a(5) = 11, a(6) = 23, a(7) = 47, a(8) = 59, a(9) = 83, a(10) = 107.
%Y Cf. A090801, A079148, A005385.
%K nonn
%O 1,1
%A _Alexander Adamchuk_, Jul 28 2006