A230641 a(n) = n + (sum of digits in base-3 representation of n).

0, 2, 4, 4, 6, 8, 8, 10, 12, 10, 12, 14, 14, 16, 18, 18, 20, 22, 20, 22, 24, 24, 26, 28, 28, 30, 32, 28, 30, 32, 32, 34, 36, 36, 38, 40, 38, 40, 42, 42, 44, 46, 46, 48, 50, 48, 50, 52, 52, 54, 56, 56, 58, 60, 56, 58, 60, 60, 62, 64, 64, 66, 68, 66, 68, 70, 70, 72, 74, 74, 76, 78, 76, 78, 80, 80, 82, 84, 84, 86, 88, 82

Offset

0,2

Comments

The image of this sequence is the set of nonnegative even numbers (A005843). Joshi (1973) proved that the sequence of base-q self numbers (analogous to A003052) is the sequence of odd numbers (A005408) for all odd q. - Amiram Eldar, Nov 28 2020

References

V. S. Joshi, Ph.D. dissertation, Gujarat Univ., Ahmedabad (India), October, 1973.

József Sándor and Borislav Crstici, Handbook of Number theory II, Kluwer Academic Publishers, 2004, Chapter 4, p. 384-386.

Links

Donovan Johnson, Table of n, a(n) for n = 0..10000

Index entries for Colombian or self numbers and related sequences

Formula

a(n) = n + A053735(n). - Amiram Eldar, Nov 28 2020

Mathematica

Table[n + Plus @@ IntegerDigits[n, 3], {n, 0, 100}] (* Amiram Eldar, Nov 28 2020 *)

Prog

(Haskell)
a230641 n = a053735 n + n  -- Reinhard Zumkeller, May 19 2015

Crossrefs

Related base-3 sequences: A053735, A134451, A230641, A230642, A230643, A230853, A230854, A230855, A230856, A230639, A230640, A010063 (trajectory of 1)

Cf. A228088, A010061, A230091, A230092, A227915.

Sequence in context: A159634 A186690 A002131 * A373800 A063200 A063224

Adjacent sequences: A230638 A230639 A230640 * A230642 A230643 A230644

Keyword

nonn,base

Author

N. J. A. Sloane, Oct 31 2013

Status

approved