A366474 Where n appears in A337136, or -1 if n never appears.

1, 2, 3, 5, 4, 6, 8, 7, 9, 10, 35, 13, 22, 16, 18, 19, 33, 23, 11, 25, 27, 26, 64, 29, 32, 31, 34, 36, 12, 37, 20, 38, 40, 39, 44, 42, 45, 46, 43, 47, 14, 48, 28, 49, 51, 50, 21, 53, 52, 55, 56, 58, 15, 59, 61, 60, 62, 63, 228, 65, 99, 24, 69, 68, 67, 71, 17, 76

Offset: 1

Author

N. J. A. Sloane, Oct 26 2023

Keywords

• nonn

Links

• Michael De Vlieger, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A337136.

Programs

Mathematica

nn = 120; c[_] := 0; Array[Set[{a[#], c[#]}, {#, #}] &, 2]; Set[{i, j, u}, Range[3]]; s = i + j;
Do[k = u; While[Or[c[k] > 0, CoprimeQ[s, k]], k++];
  Set[{a[n], c[k], i, j, s}, {k, n, j, k, j + k}];
  If[k == u, While[c[u] > 0, u++]], {n, 3, nn}];
TakeWhile[Array[c, nn], # > 0 &] (* Michael De Vlieger, Oct 26 2023 *)