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A163756
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14 times triangular numbers.
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2
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0, 14, 42, 84, 140, 210, 294, 392, 504, 630, 770, 924, 1092, 1274, 1470, 1680, 1904, 2142, 2394, 2660, 2940, 3234, 3542, 3864, 4200, 4550, 4914, 5292, 5684, 6090, 6510, 6944, 7392, 7854, 8330, 8820, 9324, 9842, 10374, 10920, 11480, 12054, 12642, 13244, 13860
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| Sequence found by reading the line from 0, in the direction 0, 14,... and the same line from 0, in the direction 0, 42,..., in the square spiral whose vertices are the generalized 16-gonal numbers. - Omar E. Pol, Oct 03 2011
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FORMULA
| a(n)=7*n*(n+1) = 14*A000217(n).
G.f.: 14*x/(1-x)^3.
a(n) = 7*n^2 + 7*n = 7*A002378(n) = 2*A024966(n) = A069127(n+1) - 1. - Omar E. Pol, Oct 03 2011
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MATHEMATICA
| Table[7*n*(n-1), {n, 100}] (* From Vladimir Joseph Stephan Orlovsky, Jul 06 2011 *)
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CROSSREFS
| Cf. A000217.
Sequence in context: A199710 A064512 A118237 * A005587 A120714 A041378
Adjacent sequences: A163753 A163754 A163755 * A163757 A163758 A163759
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KEYWORD
| nonn,easy
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 03 2009
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EXTENSIONS
| Extended by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 06 2009
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