A361513 Novel terms in A361511, in order of appearance.

1, 2, 3, 4, 5, 6, 7, 8, 11, 9, 10, 13, 15, 12, 17, 19, 21, 24, 16, 18, 14, 23, 29, 20, 27, 22, 26, 28, 35, 32, 25, 30, 34, 36, 33, 31, 44, 38, 42, 37, 45, 39, 51, 49, 60, 41, 50, 43, 40, 46, 48, 52, 54, 58, 62, 53, 56, 59, 64, 65, 57, 55, 61, 47, 68, 63, 74, 72, 67, 80, 78

Offset: 1

Author

N. J. A. Sloane, Apr 08 2023

Keywords

• nonn

Comments

By definition the terms are distinct. It is an obvious conjecture that every number eventually appears, but is there a proof?

Links

• Michael De Vlieger, Table of n, a(n) for n = 1..17905 (All novel terms in a(n) for n = 1..2^24)

Crossrefs

Cf. A361511, A361512.

Programs

Mathematica

nn = 615; 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[#]]; c[#] = True) &[a[n - 1]], {n, 2, nn}] ][[-1, -1]] (* Michael De Vlieger, Apr 08 2023 *)