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A157221
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A Eulerian tent triangle sequence: tent function: f(n,m)=If[k <= Floor[n/2], k, n - k]; t(n,m)=Eulerian[n*f[n, m], f[n, m]].
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0
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1, 1, 1, 1, 4, 1, 1, 11, 11, 1, 1, 26, 14608, 26, 1, 1, 57, 152637, 152637, 57, 1, 1, 120, 1479726, 251732291184, 1479726, 120, 1, 1, 247, 13824739, 16871482830550, 16871482830550, 13824739, 247, 1, 1, 502, 126781020, 1103881308184906
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OFFSET
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0,5
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COMMENTS
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Row sums are:
{1, 2, 6, 24, 14662, 305390, 251735250878, 33742993311074,
113909685422248854462458, 144084186112517513027508010,
4826601749538111416289955703874773044570,...}.
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LINKS
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Table of n, a(n) for n=0..39.
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FORMULA
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Tent function: f(n,m)=If[k <= Floor[n/2], k, n - k]; t(n,m)=Eulerian[n*f[n, m], f[n, m]].
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EXAMPLE
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{1},
{1, 1},
{1, 4, 1},
{1, 11, 11, 1},
{1, 26, 14608, 26, 1},
{1, 57, 152637, 152637, 57, 1},
{1, 120, 1479726, 251732291184, 1479726, 120, 1},
{1, 247, 13824739, 16871482830550, 16871482830550, 13824739, 247, 1},
{1, 502, 126781020, 1103881308184906, 113909683214485984529600, 1103881308184906, 126781020, 502, 1},
{1, 1013, 1151775897, 71394276041525549, 72042092984864479320451545, 72042092984864479320451545, 71394276041525549, 1151775897, 1013, 1},
{1, 2036, 10414216090, 4591921534898186048, 45271666954175790151474783510, 4826601749447568082372420280481198669200, 45271666954175790151474783510, 4591921534898186048, 10414216090, 2036, 1}
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MATHEMATICA
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Clear[t, n, k];
t[n_, k_] := Sum[(-1)^j Binomial[n + 1, j](k + 1 - j)^n, {j, 0, k + 1}];
f[n_, k_] := If[k <= Floor[n/2], k, n - k];
Table[Table[t[n*f[n, k] + 1, f[n, k]], {k, 0, n}], {n, 0, 10}];
Flatten[%]
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CROSSREFS
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Sequence in context: A174526 A008292 A174036 * A146967 A173152 A156049
Adjacent sequences: A157218 A157219 A157220 * A157222 A157223 A157224
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KEYWORD
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nonn,tabl,uned
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AUTHOR
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Roger L. Bagula, Feb 25 2009
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STATUS
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approved
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