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A058920
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2n^4 + 2n^3 + 3n^2 + 2n + 1.
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1
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1, 10, 65, 250, 697, 1586, 3145, 5650, 9425, 14842, 22321, 32330, 45385, 62050, 82937, 108706, 140065, 177770, 222625, 275482, 337241, 408850, 491305, 585650, 692977, 814426, 951185, 1104490, 1275625, 1465922, 1676761, 1909570, 2165825
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| On a 2n X (n^2 - n + 1) X n^2 cuboid (with n >= 3) there are six pairs of points with the maximum surface distance between them: the four pairs of opposite corners and the opposite pairs of points on the smallest faces 1 in from the mid-points of the shortest edges; this maximum surface distance is sqrt(a(n)).
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LINKS
| Harry J. Smith, Table of n, a(n) for n=0,...,500
Source
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FORMULA
| G.f.: (1+5*x+25*x^2+15*x^3+2*x^4)/(1-5*x+10*x^2-10*x^3+5*x^4-x^5). [Colin Barker, Jan 01 2012]
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PROG
| (PARI) { for (n = 0, 500, write("b058920.txt", n, " ", 2*n^4 + 2*n^3 + 3*n^2 + 2*n + 1); ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Jun 24 2009]
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CROSSREFS
| For n >= 2 the sequence is a subsequence of A007692.
Sequence in context: A144041 A033863 A033908 * A059598 A133715 A160458
Adjacent sequences: A058917 A058918 A058919 * A058921 A058922 A058923
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KEYWORD
| nonn
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AUTHOR
| Henry Bottomley (se16(AT)btinternet.com), Jan 11 2001
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