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A343829
Distinct values of gcd(B(2*j), B(2*j+2)) in the order of their appearance, where B(k) = A027641(k).
0
1, 587, 491, 37, 103, 59, 131, 67, 283, 101, 691, 157, 617, 593, 149, 233, 683, 271, 263, 307, 577, 653, 379, 257, 467, 293, 21719, 541, 1721, 631, 3617, 409, 839, 463
OFFSET
1,2
COMMENTS
Conjecture: all terms greater than 1 are irregular primes (A000928) or a product of irregular primes.
MATHEMATICA
a = Numerator@ BernoulliB@ 2; b = Numerator@ BernoulliB@ 4; k = 6; lst = {}; While[k < 75001, a = b; b = Numerator@ BernoulliB@ k; g = GCD[a, b]; If[ !MemberQ[ lst, g], AppendTo[lst, g]]; k += 2]; lst
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Robert G. Wilson v, Apr 30 2021
STATUS
approved