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A130850
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Triangle T(n,k), 0<=k<=n, read by rows given by [1,1,2,2,3,3,4,4,5,5,...] DELTA [1,0,2,0,3,0,4,0,5,0,6,0,...] where DELTA is the operator defined in A084938 .
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1
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1, 1, 1, 2, 3, 1, 6, 12, 7, 1, 24, 60, 50, 15, 1, 120, 360, 390, 180, 31, 1, 720, 2520, 3360, 2100, 602, 63, 1, 5040, 20160, 31920, 25200, 10206, 1932, 127, 1, 40320, 181440, 332640, 317520, 166824, 46620, 6050, 255, 1, 362880, 1814400, 3780000, 4233600
(list; table; graph; refs; listen; history; internal format)
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OFFSET
| 0,4
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COMMENTS
| Triangle given by A123125*A007318 (as infinite lower triangular matrices), A123125 = Euler's triangle, A007318 = Pascal's triangle ; A007318*A123125 gives A046802 . Essentially reverse of A028246 .
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FORMULA
| T(n,k)=(-1)^k*A075263(n,k). T(n,k)=(n-k)!*A008278(n+1,k+1).
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EXAMPLE
| Triangle begins:
1;
1, 1;
2, 3, 1;
6, 12, 7, 1;
24, 60, 50, 15, 1;
120, 360, 390, 180, 31, 1;
720, 2520, 3360, 2100, 602, 63, 1;
5040, 20160, 31920, 25200, 10206, 1932, 127, 1;
40320, 181440, 332640, 317520, 166824, 46620, 6050, 255, 1;
362880, 1814400, 3780000, 4233600, 2739240, 1020600, 204630, 18660, 511, 1 ;...
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CROSSREFS
| Cf. A000142 A001710 A005460 A005461 A005462 A005463 A005464.
Sequence in context: A107416 A105613 A135894 * A075263 A130405 A058372
Adjacent sequences: A130847 A130848 A130849 * A130851 A130852 A130853
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KEYWORD
| nonn,tabl
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AUTHOR
| Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Aug 20 2007
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