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A361512
Indices of novel terms in A361511.
4
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
1,2
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..17905 (all terms m <= 2^24)
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 *)
CROSSREFS
Cf. A361511.
Sequence in context: A139130 A219087 A186705 * A361516 A361515 A072154
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Apr 08 2023
STATUS
approved