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Search: id:A152745
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| A152745 |
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5 times hexagonal numbers: 5n(2n-1). |
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+0
4
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| 0, 5, 30, 75, 140, 225, 330, 455, 600, 765, 950, 1155, 1380, 1625, 1890, 2175, 2480, 2805, 3150, 3515, 3900, 4305, 4730, 5175, 5640, 6125, 6630, 7155, 7700, 8265, 8850, 9455, 10080, 10725, 11390, 12075, 12780, 13505, 14250, 15015
(list; graph; listen)
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OFFSET
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0,2
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FORMULA
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a(n) = 10n^2 - 5n = A000384(n)*5.
a(n)=20*n+a(n-1)-35 (with a(1)=0) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 13 2009]
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EXAMPLE
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For n=2, a(2)=20*2+0-35=5; n=3, a(3)=20*3+5-35=30; n=4, a(4)=20*4+30-35=75 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 13 2009]
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MATHEMATICA
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s=0; lst={s}; Do[s+=n; AppendTo[lst, s], {n, 5, 8!, 20}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Apr 03 2009]
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CROSSREFS
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Cf. A000384, A085250, A152746.
Sequence in context: A097252 A043886 A044463 this_sequence A164015 A128302 A071252
Adjacent sequences: A152742 A152743 A152744 this_sequence A152746 A152747 A152748
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KEYWORD
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easy,nonn,new
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AUTHOR
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Omar E. Pol (info(AT)polprimos.com), Dec 12 2008
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