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A098230
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75-gonal numbers: n(73n-71)/2.
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4
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0, 1, 75, 222, 442, 735, 1101, 1540, 2052, 2637, 3295, 4026, 4830, 5707, 6657, 7680, 8776, 9945, 11187, 12502, 13890, 15351, 16885, 18492, 20172, 21925, 23751, 25650, 27622, 29667, 31785, 33976, 36240, 38577, 40987, 43470, 46026, 48655, 51357, 54132, 56980, 59901, 62895, 65962, 69102, 72315, 75601, 78960, 82392, 85897, 89475
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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COMMENTS
| Similar to 21-gonal and 15-gonal numbers.
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LINKS
| Index to sequences with linear recurrences with constant coefficients, signature (3,-3,1)
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FORMULA
| G.f. -x*(1+72*x) / (x-1)^3 . - R. J. Mathar, Feb 05 2011
a(n)=n(73n-71)/2.
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MAPLE
| A098230 := proc(n) n*(73*n-71)/2 ; end proc:
seq(A098230(n), n=0..20) ; # R. J. Mathar, Feb 04 2011
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PROG
| (MAGMA) [ n*(73*n - 71)/2: n in [0..50] ]; // From Vincenzo Librandi, Feb 04 2011]
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CROSSREFS
| Cf. n-gonal numbers A000217, A000290, A000326, A000566, A000567, A001106, A001107, A051682, A051624, A051865-A051876, A098923, A098924, A098140.
Sequence in context: A044788 A003503 A201916 * A174685 A158742 A158765
Adjacent sequences: A098227 A098228 A098229 * A098231 A098232 A098233
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KEYWORD
| nonn,easy
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AUTHOR
| Parthasarathy Nambi (PachaNambi(AT)yahoo.com), Oct 25 2004
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