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A098140
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63-gonal numbers: n(61n-59)/2.
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3
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1, 63, 186, 370, 615, 921, 1288, 1716, 2205, 2755, 3366, 4038, 4771, 5565, 6420, 7336, 8313, 9351, 10450, 11610, 12831, 14113, 15456, 16860, 18325, 19851, 21438, 23086, 24795, 26565, 28396, 30288, 32241, 34255, 36330, 38466
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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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
| a(n) = n(61n-59)/2.
G.f.: (1+60*x)/(1-x)^3. - Bruno Berselli, Feb 04 2011
a(0)=1, a(1)=63, a(2)=186, a(n)=3*a(n-1)-3*a(n-2)+a(n-3) [From Harvey P. Dale, June 09 2011]
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MATHEMATICA
| Table[n(61n - 59)/2, {n, 1, 50}] - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Feb 28 2006
LinearRecurrence[{3, -3, 1}, {1, 63, 186}, 50] (* From Harvey P. Dale, June 09 2011 *)
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CROSSREFS
| Cf. n-gonal numbers A000217, A000290, A000326, A000566, A000567, A001106, A001107, A051682, A051624, A051865-A051876, A098923, A098924, A098230.
Sequence in context: A044395 A044776 A077263 * A008895 A008874 A045112
Adjacent sequences: A098137 A098138 A098139 * A098141 A098142 A098143
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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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EXTENSIONS
| More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Feb 28 2006
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