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A004163 Pentagonal numbers written backwards. 1
0, 1, 5, 21, 22, 53, 15, 7, 29, 711, 541, 671, 12, 742, 782, 33, 673, 524, 774, 235, 95, 156, 517, 287, 258, 529, 1001, 801, 2611, 7421, 5331, 6241, 251, 7161, 7171, 281, 6291, 5302, 7412, 2622, 832, 1052, 5262, 2572, 2882, 5103, 1513, 923, 2343, 7753, 5273 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..10000

FORMULA

a(n) = A004086(A000326(n)). - Michel Marcus, Apr 05 2014

MAPLE

a:= n-> (s-> parse(cat(s[-i]$i=1..length(s))))(""||(n*(3*n-1)/2)):

seq(a(n), n=0..50);  # Alois P. Heinz, Apr 09 2015

CROSSREFS

Cf. A000326.

Sequence in context: A263130 A165204 A043053 * A113410 A099654 A195959

Adjacent sequences:  A004160 A004161 A004162 * A004164 A004165 A004166

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane

EXTENSIONS

Initial 0 and terms after a(43) from Eric M. Schmidt, Apr 04 2014

STATUS

approved

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Last modified March 19 04:23 EDT 2019. Contains 321311 sequences. (Running on oeis4.)