A361512 Indices of novel terms in A361511.

1, 3, 5, 7, 9, 12, 14, 18, 21, 25, 28, 32, 39, 42, 47, 53, 59, 67, 71, 77, 80, 88, 94, 100, 106, 115, 120, 128, 134, 142, 147, 154, 161, 170, 178, 187, 196, 205, 217, 226, 236, 246, 256, 266, 280, 287, 302, 313, 327, 334, 348, 359, 374, 383, 394, 406, 416, 431

Offset: 1

Author

N. J. A. Sloane, Apr 08 2023

Keywords

• nonn

Links

• Michael De Vlieger, Table of n, a(n) for n = 1..17905 (all terms m <= 2^24)

Crossrefs

Cf. A361511.

Programs

Mathematica

nn = 432; c[] = False; f[n] := DivisorSigma[0, n]; a[1] = m = 1; Reap[Do[(If[c[#], a[n] = # + f[a[m]] ; m++, a[n] = f[#] ; Sow[n - 1]]; c[#] = True) &[a[n - 1]], {n, 2, nn}] ][[-1, -1]] (* Michael De Vlieger, Apr 08 2023 *)