A337197 Position of the first occurrence of n in A337196, where A337196(x) is the 3-adic valuation of 1+A000265(sigma(x)).

1, 19, 67, 211, 643, 3667, 5827, 17491, 104971, 628123, 1795063, 2759719, 4251523, 12754579, 83086924

Offset: 0

Author

Antti Karttunen and David A. Corneth, Aug 18 2020

Keywords

• nonn
• more

Comments

a(16) = 393475036, but a(15) is larger than that, thus the sequence is nonmonotonic.

Crossrefs

Cf. A004394, A337196.

Cf. also A200849.

Programs

Mathematica

With[{s = Array[IntegerExponent[1 + #/2^IntegerExponent[#, 2], 3] &@ DivisorSigma[1, #] &, 10^6]}, Array[FirstPosition[s, #][[1]] &, Max[s] + 1, 0]] (* Michael De Vlieger, Feb 22 2021 *)

Formula

For all n >= 0, A337196(a(n)) = n, with no n occurring in A337196 before a(n).