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A069174
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Centered 23-gonal numbers.
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0
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1, 24, 70, 139, 231, 346, 484, 645, 829, 1036, 1266, 1519, 1795, 2094, 2416, 2761, 3129, 3520, 3934, 4371, 4831, 5314, 5820, 6349, 6901, 7476, 8074, 8695, 9339, 10006
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| E. Weisstein, Centered Polygonal Numbers
Index entries for sequences related to centered polygonal numbers
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FORMULA
| a(n) = (23n^2 - 23n + 2)/2
a(n)=23*n+a(n-1)-23 (with a(1)=1) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 08 2010]
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EXAMPLE
| For n=2, a(2)=23*2+1-23=24; n=3, a(3)=23*3+24-23=70; n=4, a(4)=23*4+70-23=139 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 08 2010]
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MATHEMATICA
| FoldList[#1 + #2 &, 1, 23 Range@ 45] (* Robert G. Wilson v, Feb 02 2011 *)
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CROSSREFS
| Cf. A005448, A001844, A005891, A003215, A069099, A069125, A069133, A069126, A069127, A069128, A069129, A069130, A069131, A069132.
Sequence in context: A043934 A087406 A051876 * A124717 A126378 A006352
Adjacent sequences: A069171 A069172 A069173 * A069175 A069176 A069177
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KEYWORD
| easy,nonn
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AUTHOR
| Terrel Trotter, Jr. (ttrotter(AT)telesal.net), Apr 09 2002
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