A076887 Sum of divisors of nonzero palindromic numbers.

1, 3, 4, 7, 6, 12, 8, 15, 13, 12, 36, 48, 84, 72, 144, 96, 180, 156, 102, 152, 133, 132, 192, 152, 192, 260, 182, 192, 306, 378, 456, 450, 399, 728, 396, 558, 576, 518, 408, 314, 360, 494, 400, 354, 532, 374, 384, 528, 714, 936, 810, 768, 1064, 684, 930, 960

Offset

1,2

Links

David A. Corneth, Table of n, a(n) for n = 1..10000 (first 1000 terms from Harvey P. Dale)

Formula

a(n) = A000203(A002113(n+1)). - Omar E. Pol, Dec 08 2019

Example

a(11) = 36 because 36 is the sum of divisors of 11th nonzero palindromic number (i.e. 22).

Mathematica

DivisorSigma[1, #]&/@Select[Range[500], PalindromeQ] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Mar 06 2018 *)

Crossrefs

Cf. A000203, A002113.

Sequence in context: A168338 A034690 A069192 * A351395 A140782 A284587

Adjacent sequences: A076884 A076885 A076886 * A076888 A076889 A076890

Keyword

base,nonn,look

Author

Shyam Sunder Gupta, Nov 25 2002

Extensions

Both title and example clarified by Omar E. Pol, Dec 08 2019

Status

approved