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0, 12, 32, 60, 96, 140, 192, 252, 320, 396, 480, 572, 672, 780, 896, 1020, 1152, 1292, 1440, 1596, 1760, 1932, 2112, 2300, 2496, 2700, 2912, 3132, 3360, 3596, 3840, 4092, 4352, 4620, 4896, 5180, 5472, 5772, 6080, 6396, 6720, 7052, 7392, 7740, 8096, 8460
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| R. E. Borcherds, E. Freitag, R. Weissauer, A Siegel cusp form of degree 12 and weight 12, arXiv:math/9805132, row A_2 page 6.
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FORMULA
| O.g.f.: 4-12/(-1+x)^2-8/(-1+x)^3 . a(n) = 4*A005563(n-1). - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 24 2008
a(n)=a(n-1)+8*n-4 (with a(1)=0) [From Vincenzo Librandi, Nov 23 2010]
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EXAMPLE
| Geometry: denote castle by x.
From
xx
xx
we get (2*1)^2-4=0
From
******
******
**xx**
**xx**
******
******
we get (2*3)^2-4=32
From (chess)
********
********
********
***xx***
***xx***
********
********
********
we get 8*8-4=60 [(2*4)^2-4=60]
etc...
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MAPLE
| seq((2*k)^2-4, k=1..46);
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MATHEMATICA
| lst={}; Do[AppendTo[lst, (2*n)^2-4], {n, 1, 5!}]; lst...and/or... s=-4; lst={}; Do[s+=n+1; AppendTo[lst, s], {n, 3, 6!, 8}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Oct 25 2008]
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CROSSREFS
| Sequence in context: A071336 A051519 A166959 * A177721 A081268 A188183
Adjacent sequences: A134579 A134580 A134581 * A134583 A134584 A134585
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KEYWORD
| nonn
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AUTHOR
| Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jan 23 2008
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