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A256650 30-gonal pyramidal numbers: a(n) = n*(n+1)*(28*n-25)/6. 2
0, 1, 31, 118, 290, 575, 1001, 1596, 2388, 3405, 4675, 6226, 8086, 10283, 12845, 15800, 19176, 23001, 27303, 32110, 37450, 43351, 49841, 56948, 64700, 73125, 82251, 92106, 102718, 114115, 126325, 139376, 153296, 168113, 183855, 200550, 218226, 236911, 256633 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

See comments in A256645.

This sequence is related to A051868 by a(n) = n*A051868(n) - Sum_{i=0..n-1} A051868(i). [Bruno Berselli, Apr 09 2015]

REFERENCES

E. Deza and M. M. Deza, Figurate numbers, World Scientific Publishing (2012), page 93 (28th row of the table).

LINKS

Luciano Ancora, Table of n, a(n) for n = 0..1000

Luciano Ancora, Polygonal and Pyramidal numbers, Section 3.

Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).

FORMULA

G.f.: x*(1 + 27*x)/(1 - x)^4.

a(n) = A000292(n) + 27*A000292(n-1).

MATHEMATICA

Table[n (n + 1) (28 n - 25)/6, {n, 0, 40}]

LinearRecurrence[{4, -6, 4, -1}, {0, 1, 31, 118}, 40] (* Vincenzo Librandi, Apr 08 2015 *)

PROG

(MAGMA) [n*(n+1)*(28*n-25)/6: n in [0..50]]; // Vincenzo Librandi, Apr 08 2015

CROSSREFS

Partial sums of A254474.

Cf. similar sequences listed in A237616.

Cf. A000292, A051868.

Sequence in context: A204735 A254283 A010019 * A131550 A158558 A160893

Adjacent sequences:  A256647 A256648 A256649 * A256651 A256652 A256653

KEYWORD

nonn,easy

AUTHOR

Luciano Ancora, Apr 07 2015

STATUS

approved

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Last modified February 16 21:22 EST 2019. Contains 320199 sequences. (Running on oeis4.)