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A152994
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Nine times hexagonal numbers: 9*n*(2*n-1).
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1
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0, 9, 54, 135, 252, 405, 594, 819, 1080, 1377, 1710, 2079, 2484, 2925, 3402, 3915, 4464, 5049, 5670, 6327, 7020, 7749, 8514, 9315, 10152, 11025, 11934, 12879, 13860, 14877, 15930, 17019, 18144, 19305, 20502, 21735, 23004, 24309
(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, 9,..., in the square spiral whose vertices are the generalized hendecagonal numbers A195160. - Omar E. Pol, Sep 18 2011
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FORMULA
| a(n) = 18*n^2 - 9*n = A000384(n)*9 = A094159(n)*3.
a(n) = a(n-1)+36*n-27 (with a(0)=0). [From Vincenzo Librandi, Dec 15 2010]
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CROSSREFS
| Cf. A000384, A094159.
Sequence in context: A144040 A052108 A093846 * A034719 A013567 A073974
Adjacent sequences: A152991 A152992 A152993 * A152995 A152996 A152997
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KEYWORD
| easy,nonn
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AUTHOR
| Omar E. Pol (info(AT)polprimos.com), Dec 22 2008
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