1,2

a(1) = 1; for n >= 1, a(n+1) = a(n) + sum of its digits.

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Index entries for Colombian or self numbers and related sequences

(Haskell)

a230286 = (flip div 3) . a016052

Cf. A004207, A016052, A230287 (first differences).

Sequence in context: A175302 A288521 A067940 * A215099 A022768 A229973

Adjacent sequences: A230283 A230284 A230285 * A230287 A230288 A230289

nonn,base

Reinhard Zumkeller and N. J. A. Sloane, Oct 16 2013

approved