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%I #15 Dec 13 2014 00:37:46
%S 1,5,7,11,25,13,17,35,19,23,55,29,49,125,31,37,65,77,41,85,43,47,175,
%T 53,121,95,59,91,115,61,67,275,119,71,145,73,79,245,143,83,625,89,133,
%U 155,97,187,185,161,101,325,103,107,385,109,113,205,127,203,425,209,169,215,343,131,235,137,253,875,139,149,265,221,217,605,151
%N Odd bisection of A003961: Replace in 2n-1 each prime factor p(k) with prime p(k+1).
%C This has the same terms as A007310 (Numbers congruent to 1 or 5 mod 6), but in different order. Apart from 1, they are the numbers that occur below the first two rows of arrays like A246278 and A083221 (A083140).
%H Antti Karttunen, <a href="/A249735/b249735.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A003961(2n - 1).
%F a(n) = A007310(A249746(n)). [Permutation of A007310, Numbers congruent to 1 or 5 mod 6.]
%F Other identities. For all n >= 1:
%F A007310(n) = a(A249745(n)).
%F A246277(5*a(A048673(n))) = n.
%F A246277(5*a(n)) = A064216(n).
%o (Scheme) (define (A249735 n) (A003961 (+ n n -1)))
%Y Cf. A249734 (the other bisection of A003961).
%Y Cf. also A007310 (A038179), A249746.
%K nonn
%O 1,2
%A _Antti Karttunen_, Nov 23 2014