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%I #48 Mar 09 2020 15:32:53
%S 1,2,3,5,15,51,305,1059,4083,117737,3775459,19465955,952896293,
%T 13613071346,14565967639,112716155924,11073544747197,637616871476643,
%U 11027737075804991,3056322734187753262,542921033413649799807,8189660342217563295915,515222301162241572644117
%N a(1) = 1, a(2) = 2. Thereafter a(n+1) is the smallest number k such that A001414(k) = a(n) + a(n-1).
%H Jinyuan Wang, <a href="/A330821/b330821.txt">Table of n, a(n) for n = 1..200</a>
%F a(n+1) = A056240(a(n) + a(n-1)).
%e sopfr(3) = 3 = 2 + 1, sopfr(15) = 8 = 3 + 5, etc.
%t s[1] = 0; s[n_] := Plus @@ Times @@@ FactorInteger@n; a[1] = 1; a[2] = 2; a[n_] := a[n] = Module[{k = 1, sum = a[n - 1] + a[n - 2]}, While[s[k] != sum, k++]; k]; Array[a, 10] (* _Amiram Eldar_, Jan 02 2020 *)
%Y Cf. A000045, A001414, A056240.
%K nonn
%O 1,2
%A _David James Sycamore_, Jan 02 2020
%E Data corrected by and more terms from _Amiram Eldar_ and _David A. Corneth_, Jan 02 2020
%E Data corrected by _Jinyuan Wang_, Mar 08 2020