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A144275 Lower triangular array called S2hat(-2) related to partition number array A144274. +0
6
1, 2, 1, 10, 2, 1, 80, 14, 2, 1, 880, 100, 14, 2, 1, 12320, 1140, 108, 14, 2, 1, 209440, 14880, 1180, 108, 14, 2, 1, 4188800, 249280, 15400, 1196, 108, 14, 2, 1, 96342400, 4801280, 255400, 15480, 1196, 108, 14, 2, 1, 2504902400, 108574400, 4888960, 256440, 15512 (list; table; graph; listen)
OFFSET

1,2

COMMENT

If in the partition array M32khat(-2)= A144274 entries with the same parts number m are summed one obtains this triangle of numbers S2hat(-2). In the same way the Stirling2 triangle A008277 is obtained from the partition array M_3 = A036040.

The first three columns are A008544, A144277, A144278.

REFERENCES

W. Lang, Combinatorial Interpretation of Generalized Stirling Numbers, preprint Oct 2008.

LINKS

W. Lang, First 10 rows of the array and more.

FORMULA

a(n,m)=sum(product(|S2(-2;j,1)|^e(n,m,q,j),j=1..n),q=1..p(n,m)) if n>=m>=1, else 0. Here p(n,m)=A008284(n,m), the number of m parts partitions of n and e(n,m,q,j) is the exponent of j in the q-th m part partition of n. |S2(-2,n,1)|= A004747(n,1) = A008544(n-1) = (3*n-4)(!^3) (3-factorials) for n>=2 and 1 if n=1.

EXAMPLE

[1];[2,1];[10,2,1];[80,14,2,1];[880,100,14,2,1];...

CROSSREFS

Row sums A144276.

A144270 (S2hat(-1)).

Sequence in context: A112691 A110169 A144274 this_sequence A011268 A163235 A142963

Adjacent sequences: A144272 A144273 A144274 this_sequence A144276 A144277 A144278

KEYWORD

nonn,easy,tabl

AUTHOR

Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de) Oct 09 2008

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Last modified December 4 08:07 EST 2009. Contains 170310 sequences.


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