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A048994 Triangle of Stirling numbers of first kind, s(n,k), n >= 0, 0<=k<=n. +0
31
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 (list; table; graph; listen)
OFFSET

1,8

COMMENT

The unsigned numbers are also called Stirling cycle numbers: |s(n,k)| = number of permutations of n objects with exactly k cycles.

Mirror image of the triangle A054654 . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Dec 30 2006

REFERENCES

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 833.

L. Comtet, Advanced Combinatorics, Reidel, 1974; Chapter V, also p. 310.

J. H. Conway and R. K. Guy, The Book of Numbers, Copernicus Press, NY, 1996, p. 93.

F. N. David, M. G. Kendall and D. E. Barton, Symmetric Function and Allied Tables, Cambridge, 1966, p. 226.

R. L. Graham, D. E. Knuth and O. Patashnik, Concrete Mathematics. Addison-Wesley, Reading, MA, 1990, p. 245.

J. Riordan, An Introduction to Combinatorial Analysis, p. 48.

LINKS

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, December 1972 [alternative scanned copy].

R. M. Dickau, Stirling numbers of the first kind

FORMULA

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

The unsigned numbers a(n, k)=|s(n, k)| satisfy a(n, k)=a(n-1, k-1)+(n-1)*a(n-1, k), n, k >= 1; a(n, 0)=a(0, k)=0; a(0, 0)=1.

Triangle (signed) = [0, -1, -1, -2, -2, -3, -3, -4, -4, ...] DELTA A000035; Triangle(unsigned) = [0, 1, 1, 2, 2, 3, 3, 4, 4, ...] DELTA A000035; where DELTA is Deleham's operator defined in A084938.

Sum_{k=0..n} (-m)^(n-k)*T(n, k) = A000142(n), A001147(n), A007559(n), A007696(n), ... for m = 1, 2, 3, 4, ... .- Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Oct 29 2005

EXAMPLE

1; 0,1; 0,-1,1; 0,2,-3,1; 0,-6,11,-6,1; 0,24,-50,35,-10,1; ...

PROGRAM

(PARI) a(n, k) = if(k<0|k>n, 0, if(n==0, 1, (n-1)*a(n-1, k)+a(n-1, k-1)))

CROSSREFS

See especially A008275 which is the main entry for this triangle. Cf. A008277, A039814-A039817, A048993.

Cf. A084938.

A000142(n) = sum(|s(n, k)|) k=0..n, n >= 0.

Adjacent sequences: A048991 A048992 A048993 this_sequence A048995 A048996 A048997

Sequence in context: A100329 A081247 A005210 this_sequence A132393 A121434 A137329

KEYWORD

sign,tabl,nice

AUTHOR

njas

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Last modified May 16 23:01 EDT 2008. Contains 139884 sequences.


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