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A132393 Triangle of unsigned Stirling numbers of the first kind (see A048994), read by rows. +0
19
1, 0, 1, 0, 1, 1, 0, 2, 3, 1, 0, 6, 11, 6, 1, 0, 24, 50, 35, 10, 1, 0, 120, 274, 225, 85, 15, 1, 0, 720, 1764, 1624, 735, 175, 21, 1, 0, 5040, 13068, 13132, 6769, 1960, 322, 28, 1, 0, 40320, 109584, 118124, 67284, 22449, 4536, 546, 36, 1, 0, 362880, 1026576, 1172700 (list; table; graph; listen)
OFFSET

0,8

COMMENT

Triangle T(n,k), 0<=k<=n, read by rows given by [0,1,1,2,2,3,3,4,4,5,5,...] DELTA [1,0,1,0,1,0,1,0,1,...] where DELTA is the operator defined in A084938 .

A094645*A007318 as infinite lower triangular matrices.

Row sums are the factorial numbers. - Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Apr 18 2008

REFERENCES

Steve Roman, The Umbral Calculus, Dover Publications, New York (1984), pp. 149-150

FORMULA

T(n,k)=T(n-1,k-1)+(n-1)*T(n-1,k), n,k>=1 ; T(n,0)=T(0,k) ; T(0,0)=1 .

Sum_{k, 0<=k<=n}T(n,k)*x^(n-k)= A000012(n), A000142(n), A001147(n), A007559(n), A007696(n), A008548(n), A008542(n), A045754(n), A045755(n) for x = 0, 1, 2, 3, 4, 5, 6, 7, 8 respectively . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 13 2007

Expand 1/(1-t)^x = Sum[p(x,n)*t^n/n!,{n,0,Infinity}]; then the coefficients of the p(x,n) produce the triangle. - Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Apr 18 2008

Sum_{k=0..n}T(n,k)*2^k*x^(n-k) = A000142(n+1), A000165(n), A008544(n), A001813(n), A047055(n), A047657(n), A084947(n), A084948(n), A084949(n) for x = 1, 2, 3, 4, 5, 6, 7, 8, 9 respectively . [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Sep 18 2008]

a(n)=Sum_{k=0..n}T(n,k)*3^k*x^(n-k)= A001710(n+2), A001147(n+1), A032031(n), A008545(n), A047056(n), A011781(n), A144739(n), A144756(n), A144758(n) for x=1,2,3,4,5,6,7,8,9,respectively . [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Sep 20 2008]

Sum_{k=0..n}T(n,k)*4^k*x^(n-k)= A001715(n+3), A002866(n+1), A007559(n+1), A047053(n), A008546(n), A049308(n), A144827(n), A144828(n), A144829(n) for x=1,2,3,4,5,6,7,8,9 respectively . [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Sep 21 2008]

Sum_{k, 0<=k<=n}x^k*T(n,k) = x*(1+x)*(2+x)*...*(n-1+x), n>=1. [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Oct 17 2008]

EXAMPLE

Triangle begins:

1;

0, 1;

0, 1, 1;

0, 2, 3, 1;

0, 6, 11, 6, 1;

0, 24, 50, 35, 10, 1;

0, 120, 274, 225, 85, 15, 1 ;...

MATHEMATICA

p[t_] = 1/(1 - t)^x; Table[ ExpandAll[(n!)SeriesCoefficient[ Series[p[t], {t, 0, 30}], n]], {n, 0, 10}]; a = Table[(n!)* CoefficientList[SeriesCoefficient[ Series[p[t], {t, 0, 30}], n], x], {n, 0, 10}]; Flatten[a] - Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Apr 18 2008

CROSSREFS

Essentially a duplicate of A048994. Cf. A008275, A008277, A130534.

Sequence in context: A144633 A005210 A048994 this_sequence A121434 A137329 A004579

Adjacent sequences: A132390 A132391 A132392 this_sequence A132394 A132395 A132396

KEYWORD

nonn,tabl

AUTHOR

Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 10 2007, Oct 15 2008, Oct 17 2008

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.


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