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

1,2

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)

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 *)

Crossrefs

Cf. A361511, A361512.

Sequence in context: A354441 A354435 A358277 * A255004 A257728 A377193

Adjacent sequences: A361510 A361511 A361512 * A361514 A361515 A361516

Keyword

nonn

Author

N. J. A. Sloane, Apr 08 2023

Status

approved