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A134151
Triangle of numbers obtained from the partition array A134150.
6
1, 4, 1, 28, 4, 1, 280, 44, 4, 1, 3640, 392, 44, 4, 1, 58240, 5544, 456, 44, 4, 1, 1106560, 80640, 5992, 456, 44, 4, 1, 24344320, 1519840, 88256, 6248, 456, 44, 4, 1, 608608000, 31420480, 1631392, 90048, 6248, 456, 44, 4, 1, 17041024000, 766525760, 33293120
OFFSET
1,2
COMMENTS
This triangle is named S2(4)'.
In the same manner the unsigned Lah triangle A008297 is obtained from the partition array A130561.
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;j,1)= A007559(j) = A035469(j,1) = (3*j-2)!!!.
EXAMPLE
[1]; [4,1]; [28,4,1]; [280,44,4,1]; [3640,392,44,4,1];...
CROSSREFS
Cf. A134152 (row sums). A134272 (alternating row sums).
Cf. A134146 (S2(3)' triangle).
Sequence in context: A096206 A336913 A134150 * A264773 A119304 A114150
KEYWORD
nonn,easy,tabl
AUTHOR
Wolfdieter Lang Nov 13 2007
STATUS
approved