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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
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).
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