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A256648
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28-gonal pyramidal numbers: a(n) = n*(n+1)*(26*n-23)/6.
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2
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0, 1, 29, 110, 270, 535, 931, 1484, 2220, 3165, 4345, 5786, 7514, 9555, 11935, 14680, 17816, 21369, 25365, 29830, 34790, 40271, 46299, 52900, 60100, 67925, 76401, 85554, 95410, 105995, 117335, 129456, 142384, 156145, 170765, 186270, 202686, 220039, 238355
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OFFSET
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0,3
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COMMENTS
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REFERENCES
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E. Deza and M. M. Deza, Figurate numbers, World Scientific Publishing (2012), page 93 (26th row of the table).
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LINKS
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FORMULA
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G.f.: x*(1 + 25*x)/(1 - x)^4.
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MATHEMATICA
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Table[n (n + 1)(26 n - 23)/6, {n, 0, 40}]
LinearRecurrence[{4, -6, 4, -1}, {0, 1, 29, 110}, 40] (* Vincenzo Librandi, Apr 08 2015 *)
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PROG
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CROSSREFS
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Cf. similar sequences listed in A237616.
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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