A055947 n - reversal of base 3 digits of n (written in base 10).

0, 0, 0, 2, 0, -2, 4, 2, 0, 8, 0, -8, 8, 0, -8, 8, 0, -8, 16, 8, 0, 16, 8, 0, 16, 8, 0, 26, 0, -26, 20, -6, -32, 14, -12, -38, 32, 6, -20, 26, 0, -26, 20, -6, -32, 38, 12, -14, 32, 6, -20, 26, 0, -26, 52, 26, 0, 46, 20, -6, 40, 14, -12, 58, 32, 6, 52, 26, 0, 46, 20, -6, 64, 38, 12, 58, 32, 6, 52, 26, 0, 80, 0, -80, 56, -24, -104, 32, -48

Offset

0,4

Comments

a(n) is even.

Links

Indranil Ghosh, Table of n, a(n) for n = 0..20000

Formula

a(n) = n - A030102(n).

Example

For n = 5, the reversal of base 3 digits of n (written in base 10) is 7. So, a(5) = 5 - 7 = -2. - Indranil Ghosh, Feb 01 2017

Mathematica

Table[n-FromDigits[Reverse[IntegerDigits[n, 3]], 3], {n, 0, 90}] (* Harvey P. Dale, May 14 2022 *)

Prog

(PARI) a(n) = n - fromdigits(Vecrev(digits(n, 3)), 3); \\ Michel Marcus, Aug 09 2019

Crossrefs

Cf. A030102, A056965.

Sequence in context: A144182 A037036 A378986 * A015910 A182256 A164993

Adjacent sequences: A055944 A055945 A055946 * A055948 A055949 A055950

Keyword

base,sign

Author

Henry Bottomley, Jul 18 2000

Status

approved