A122667 a(n) = d(n)_d(n) = A122618(d(n)), where d = A000005, and A122618 = "n read in base n".

1, 2, 2, 3, 2, 4, 2, 4, 3, 4, 2, 6, 2, 4, 4, 5, 2, 6, 2, 6, 4, 4, 2, 8, 3, 4, 4, 6, 2, 8, 2, 6, 4, 4, 4, 9, 2, 4, 4, 8, 2, 8, 2, 6, 6, 4, 2, 10, 3, 6, 4, 6, 2, 8, 4, 8, 4, 4, 2, 14, 2, 4, 6, 7, 4, 8, 2, 6, 4, 8, 2, 14, 2, 4, 6, 6, 4, 8, 2, 10, 5, 4, 2, 14, 4, 4, 4, 8, 2, 14, 4, 6, 4, 4, 4, 14, 2, 6, 6, 9

Offset

1,2

Comments

See A122618 for notation.

Only terms >= 12 are different from d(n), the first one is a(60). - M. F. Hasler, Apr 22 2015

Links

Antti Karttunen, Table of n, a(n) for n = 1..10000

Mathematica

a[n_]:=FromDigits[IntegerDigits[tau=DivisorSigma[0, n]], tau]; Array[a, 100] (* Stefano Spezia, May 03 2025 *)

Prog

(PARI) A122667(n)=A122618(numdiv(n)) \\ M. F. Hasler, Apr 22 2015

Crossrefs

Cf. A000005, A122668.

Sequence in context: A179941 A179942 A000005 * A122668 A073668 A302051

Adjacent sequences: A122664 A122665 A122666 * A122668 A122669 A122670

Keyword

nonn,base

Author

N. J. A. Sloane, Sep 22 2006

Status

approved