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%I #15 Dec 11 2019 06:48:50
%S 1,2,4,5,8,11,12,17,18,37,24,53,30,89,39,71,42,101,45,179,57,137,72,
%T 193,60,233,84,257,90,251,117,401,123,311,144,373,120,347,105,457,162,
%U 661,150,479,180,547,237,599,165,617,264,641,288,683,195,907,231,881
%N Least number m such that A035026(m) = n.
%C The upper branch visible in the scatterplot of the first terms corresponds to odd-indexed terms. - _Rémy Sigrist_, Jan 31 2018
%H Rémy Sigrist, <a href="/A298990/b298990.txt">Table of n, a(n) for n = 0..10000</a>
%H Rémy Sigrist, <a href="/A298990/a298990.txt">C++ program for A298990</a>
%e 2* 2 = 2 + 2, so a(1) = 2.
%e 2* 4 = 3 + 5 = 5 + 3, so a(2) = 4.
%e 2* 5 = 3 + 7 = 5 + 5 = 7 + 3, so a(3) = 5.
%e 2* 8 = 3 + 13 = 5 + 11 = 11 + 5 = 13 + 3, so a(4) = 8.
%e 2*11 = 3 + 19 = 5 + 17 = 11 + 11 = 17 + 5 = 19 + 3, so a(5) = 11.
%o (C++) See Links section.
%o (PARI) nb(n) = sum(i=1, 2*n-1, isprime(i) && isprime(2*n-i));
%o a(n) = {my(k=1); while (nb(k) != n, k++); k;} \\ _Michel Marcus_, Jan 31 2018
%Y Cf. A035026.
%K nonn
%O 0,2
%A _Seiichi Manyama_, Jan 31 2018
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