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A145364
Lower triangular array, called S1hat(-2), related to partition number array A145363.
4
1, 2, 1, 2, 2, 1, 0, 6, 2, 1, 0, 4, 6, 2, 1, 0, 4, 12, 6, 2, 1, 0, 0, 12, 12, 6, 2, 1, 0, 0, 8, 28, 12, 6, 2, 1, 0, 0, 8, 24, 28, 12, 6, 2, 1, 0, 0, 0, 24, 56, 28, 12, 6, 2, 1, 0, 0, 0, 16, 56, 56, 28, 12, 6, 2, 1, 0, 0, 0, 16, 48, 120, 56, 28, 12, 6, 2, 1, 0, 0, 0, 0, 48, 112, 120, 56, 28, 12, 6, 2, 1
OFFSET
1,2
COMMENTS
If in the partition array M31hat(-2):=A145363 entries belonging to partitions with the same parts number m are summed one obtains this triangle of numbers S1hat(-2). In the same way the signless Stirling1 triangle |A008275| is obtained from the partition array M_2 = A036039.
The first column is [1,2,2,0,0,0,...]= A008279(2,n-1), n>=1.
FORMULA
a(n,m)=sum(product(S1(-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. S1(-2,n,1)= A008279(2,n-1) = [1,2,2,0,0,0,...], n>=1.
EXAMPLE
[1];[2,1];[2,2,1];[0,6,2,1];[0,4,6,2,1];...
CROSSREFS
A145365 (row sums).
Sequence in context: A145363 A071429 A264398 * A284978 A175862 A261083
KEYWORD
nonn,easy,tabl
AUTHOR
Wolfdieter Lang Oct 17 2008
STATUS
approved