A222816 Numbers k that divide the base-5 reversal of k.

8, 48, 144, 208, 248, 744, 1008, 1248, 3744, 5008, 5208, 6048, 6248, 18744, 25008, 26208, 30048, 31248, 90144, 93744, 125008, 126008, 130208, 131208, 150048, 151048, 155248, 156248, 450144, 468744, 625008, 631008, 650208, 656208, 750048, 756048, 775248, 781248

Offset

1,1

Comments

The base-B reversal of k is obtained by writing k in base B and reversing the order of the digits.

Links

N. J. A. Sloane, Table of n, a(n) for n = 1..57

Leonard F. Klosinski and Dennis C. Smolarski, On the Reversing of Digits, Math. Mag., 42 (1969), 208-210. [Gives a(1)]

N. J. A. Sloane, 2178 And All That, arXiv:1307.0453 [math.NT], 2013; Fib. Quart., 52 (2014), 99-120.

Example

8 in base 5 is 13_5; its reverse is 31_5, which is 16 in base 10, and 8 divides 16, so 8 is in the sequence.

Mathematica

Select[Range[10^6], Divisible[s=FromDigits[Reverse@IntegerDigits[#, 5], 5], #]&&s!=#&] (* Giorgos Kalogeropoulos, Aug 20 2021 *)

Prog

(PARI) isok(n) = (rdn = subst(Polrev(digits(n,  5)), x, 5)) && (rdn != n) && (rdn % n) == 0; \\ Michel Marcus, Oct 10 2014

Crossrefs

Cf. A214927, A091079.

Sequence in context: A121355 A227499 A168012 * A280056 A035471 A209443

Adjacent sequences: A222813 A222814 A222815 * A222817 A222818 A222819

Keyword

nonn,base

Author

N. J. A. Sloane, Mar 13 2013

Extensions

More terms from Alois P. Heinz, Mar 13 2013

Status

approved