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A163632 Triple and reverse digits. 20
1, 3, 9, 72, 612, 6381, 34191, 375201, 3065211, 3365919, 75779001, 300733722, 661102209, 7266033891, 37610189712, 631965038211, 3364115985981, 34975974329001, 300789229729401, 302881986763209, 726982069546809 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Vaclav Kotesovec, Table of n, a(n) for n = 1..1000

Vaclav Kotesovec, Plot of a(n)^(1/n) for n = 1..10000

MATHEMATICA

a[n_] := a[n] = If[n==1, 1, IntegerReverse[3a[n-1]]];

Array[a, 40] (* Jean-François Alcover, Jan 01 2021 *)

CROSSREFS

The following are parallel families: A000079 (2^n), A004094 (2^n reversed), A028909 (2^n sorted up), A028910 (2^n sorted down), A036447 (double and reverse), A057615 (double and sort up), A263451 (double and sort down); A000244 (3^n), A004167 (3^n reversed), A321540 (3^n sorted up), A321539 (3^n sorted down), A163632 (triple and reverse), A321542 (triple and sort up), A321541 (triple and sort down).

Cf. A132064, A045539, A132078, A132114, A132113, A133361.

Sequence in context: A018564 A004167 A321539 * A321541 A102322 A305855

Adjacent sequences:  A163629 A163630 A163631 * A163633 A163634 A163635

KEYWORD

nonn,base

AUTHOR

Dmitry Kamenetsky, Aug 02 2009

EXTENSIONS

Offset changed from 0 to 1 by Vaclav Kotesovec, Jan 03 2020

STATUS

approved

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Last modified November 30 20:17 EST 2021. Contains 349425 sequences. (Running on oeis4.)