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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, Polygonal and Pyramidal numbers, Section 3.
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.
Sequence in context: A204735 A254283 A010019 * A131550 A360805 A158558
KEYWORD
nonn,easy
AUTHOR
Luciano Ancora, Apr 07 2015
STATUS
approved

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Last modified May 16 17:27 EDT 2024. Contains 372554 sequences. (Running on oeis4.)