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Average of Eulerian numbers (A008292) and Pascal's triangle (A007318): t(n,m) = (A008292(n,m) + A007318(n,m))/2.
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%I #7 Jun 05 2018 22:33:57

%S 1,1,1,1,3,1,1,7,7,1,1,15,36,15,1,1,31,156,156,31,1,1,63,603,1218,603,

%T 63,1,1,127,2157,7827,7827,2157,127,1,1,255,7318,44145,78130,44145,

%U 7318,255,1,1,511,23938,227638,655240,655240,227638,23938,511,1

%N Average of Eulerian numbers (A008292) and Pascal's triangle (A007318): t(n,m) = (A008292(n,m) + A007318(n,m))/2.

%C Row sums are: {1, 2, 5, 16, 68, 376, 2552, 20224, 181568, 1814656, ...}.

%C If Pascal's triangle and the Eulerian numbers are both fundamental arrays, then there should be a combinatorial set "between" them.

%H G. C. Greubel, <a href="/A141689/b141689.txt">Rows n=1..100 of triangle, flattened</a>

%e {1},

%e {1, 1},

%e {1, 3, 1},

%e {1, 7, 7, 1},

%e {1, 15, 36, 15, 1},

%e {1, 31, 156, 156, 31, 1},

%e {1, 63, 603, 1218, 603, 63, 1},

%e {1, 127, 2157, 7827, 7827, 2157, 127, 1},

%e {1, 255, 7318, 44145, 78130, 44145, 7318, 255, 1},

%e {1, 511, 23938, 227638, 655240, 655240, 227638, 23938, 511, 1}

%t Table[Table[(Sum[(-1)^j Binomial[n + 1, j](k + 1 - j)^n, {j, 0, k + 1}] + Binomial[n - 1, k])/2, {k, 0, n - 1}], {n, 1, 10}]; Flatten[%]

%Y Cf. A008292, A007318.

%K nonn,tabl

%O 1,5

%A _Roger L. Bagula_, Sep 09 2008

%E Edited by _N. J. A. Sloane_, Dec 13 2008