%I #34 Jan 28 2015 11:06:31
%S 2,4,7,20,8,17,39,134,45,206,149,49,66,321,88,98,637,382,259,284,820,
%T 302,310,1102,1597,3763,1140,3432,741,532,4751,856,4855,3446,2130,
%U 3256,3407,694,2250,4878,5588,13199,15211,9040,7426,11126,5931,11699,22463,26223,37546,37602,42795,32776
%N First occurrence of 2n in A035096.
%H Robert G. Wilson v, <a href="/A247234/b247234.txt">Table of n, a(n) for n = 1..276</a>
%e a(1) = 2 since the first appearance of 2 occurs at A035096(2);
%e a(3) = 7 since the first appearance of 6 occurs at A035096(7).
%t f[n_] := Block[{p = Prime@ n}, q = 1 + 2p; While[ !PrimeQ@ q, q += 2p]; (q - 1)/p]; f[1] = 1; t = Table[0, {1000}]; k = 2; While[k < 1000000001, a = f@ k /2; If[ t[[a]] == 0, t[[a]] = k; Print[{a, k}]]; k++]]; t
%Y Cf. A035096.
%K nonn
%O 1,1
%A _Robert G. Wilson v_, Dec 28 2014
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