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A050492
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Thickened cube numbers: n*(n^2+(n-1)^2)+(n-1)*2*n*(n-1).
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3
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1, 14, 63, 172, 365, 666, 1099, 1688, 2457, 3430, 4631, 6084, 7813, 9842, 12195, 14896, 17969, 21438, 25327, 29660, 34461, 39754, 45563, 51912, 58825, 66326, 74439, 83188, 92597, 102690, 113491, 125024, 137313, 150382, 164255, 178956
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 1..10000
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FORMULA
| a(n) = n*(4*n^2-6*n+3).
a(1)=1, a(2)=14, a(3)=63, a(4)=172, a(n)=4*a(n-1)-6*a(n-2)+4*a(n-3)- a(n-4). - Harvey P. Dale, Oct 02 2011
G.f.: x*(1+10*x+13*x^2)/(1-4*x+6*x^2-4*x^3+x^4). - Colin Barker, Jan 04 2012
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EXAMPLE
| ..... * * .. * .. * *
a(2) = * .. * * .. * = 14
..... * * .. * .. * *
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MATHEMATICA
| Table[n(n^2+(n-1)^2)+(n-1)2n(n-1), {n, 40}] (* or *) LinearRecurrence[ {4, -6, 4, -1}, {1, 14, 63, 172}, 40] (* From Harvey P. Dale, Oct 02 2011 *)
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PROG
| (MAGMA) [n*(4*n^2-6*n+3): n in [1..40]]; // Vincenzo Librandi, Oct 03 2011
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CROSSREFS
| Cf. A001844, A046092, A050533.
Sequence in context: A022674 A044152 A044533 * A050396 A069964 A074354
Adjacent sequences: A050489 A050490 A050491 * A050493 A050494 A050495
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KEYWORD
| nonn,easy,nice
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AUTHOR
| Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Dec 27 1999
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