A034885 Record values of sigma(n).

1, 3, 4, 7, 12, 15, 18, 28, 31, 39, 42, 60, 72, 91, 96, 124, 168, 195, 224, 234, 252, 280, 360, 403, 480, 546, 576, 600, 744, 819, 868, 992, 1170, 1344, 1512, 1560, 1680, 1860, 1872, 2016, 2418, 2880, 3048, 3224, 3600, 3844, 4368, 4914, 5040, 5082, 5952, 6045

Offset: 1

Author

Erich Friedman

Keywords

• nonn

Comments

RECORDS transform of A000203.

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..639 from T. D. Noe)
• N. J. A. Sloane, Transforms (The RECORDS transform returns both the high-water marks and the places where they occur).

Crossrefs

Cf. A000203, A002093, A034091.

Programs

Mathematica

DeleteDuplicates[DivisorSigma[1,Range[5000]],GreaterEqual] (* Harvey P. Dale, Dec 20 2023 *)

Formula

a(n) = A000203(A002093(n)).