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A144285 Lower triangular array called S2hat(-4) related to partition number array A144284. 6
1, 4, 1, 36, 4, 1, 504, 52, 4, 1, 9576, 648, 52, 4, 1, 229824, 12888, 712, 52, 4, 1, 6664896, 286272, 13464, 712, 52, 4, 1, 226606464, 8182944, 299520, 13720, 712, 52, 4, 1, 8837652096, 266366016, 8455392, 301824, 13720, 712, 52, 4, 1, 388856692224, 10191545280, 273091392 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

If in the partition array M32khat(-4)= A144284 entries with the same parts number m are summed one obtains this triangle of numbers S2hat(-4). In the same way the Stirling2 triangle A008277 is obtained from the partition array M_3 = A036040.

The first three columns are A008546, A144339, A144340.

LINKS

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

W. Lang, Combinatorial Interpretation of Generalized Stirling Numbers, J. Int. Seqs. Vol. 12 (2009) 09.3.3.

FORMULA

a(n,m)=sum(product(|S2(-4;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(-4,n,1)|= A011801(n,1) = A008546(n-1) = (5*n-6)(!^5) (5-factorials) for n>=2 and 1 if n=1.

EXAMPLE

[1];[4,1];[36,4,1];[504,52,4,1];[9576,648,52,4,1];...

CROSSREFS

Row sums A144286.

A144280 (S2hat(-3)), A144342 (S2hat(-5)).

Sequence in context: A075804 A059844 A144284 * A091741 A061036 A144267

Adjacent sequences:  A144282 A144283 A144284 * A144286 A144287 A144288

KEYWORD

nonn,easy,tabl

AUTHOR

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

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Last modified February 17 12:36 EST 2012. Contains 206021 sequences.