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A051876
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24-gonal numbers: n(11n-10).
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27
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0, 1, 24, 69, 136, 225, 336, 469, 624, 801, 1000, 1221, 1464, 1729, 2016, 2325, 2656, 3009, 3384, 3781, 4200, 4641, 5104, 5589, 6096, 6625, 7176, 7749, 8344, 8961, 9600, 10261, 10944, 11649, 12376, 13125, 13896, 14689, 15504, 16341
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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REFERENCES
| A. H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, p. 189.
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LINKS
| Index to sequences with linear recurrences with constant coefficients, signature (3,-3,1).
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FORMULA
| a(n)=n(11n-10).
a(n)=22*n+a(n-1)-21 (with a(0)=0) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 06 2010]
G.f.: x*(1+21*x)/(1-x)^3. [Colin Barker, Jan 10 2012]
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EXAMPLE
| a(1)=22*1+0-21=1; a(2)=22*2+1-21=24; a(3)=22*3+24-21=69 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 06 2010]
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MATHEMATICA
| s=0; lst={s}; Do[s+=n++ +1; AppendTo[lst, s], {n, 0, 7!, 22}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Nov 16 2008]
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PROG
| (PARI) a(n)=n*(11*n-10) \\ Charles R Greathouse IV, Jul 19 2011
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CROSSREFS
| Cf. n-gonal numbers: A000217, A000290, A000326, A000566, A000567, A001106, A001107, A051682, A051624, A051865-A051876.
Sequence in context: A039331 A043934 A087406 * A069174 A124717 A126378
Adjacent sequences: A051873 A051874 A051875 * A051877 A051878 A051879
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KEYWORD
| nonn,easy
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com), Dec 15 1999
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