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Triangle read by rows of products of (signless) Stirling numbers of the first kind (A132393) and Stirling numbers of the second kind (A008277).
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%I #11 Jan 05 2013 08:50:11

%S 1,0,1,0,1,1,0,2,9,1,0,6,77,36,1,0,24,750,875,100,1,0,120,8494,20250,

%T 5525,225,1,0,720,111132,488824,257250,24500,441,1,0,5040,1659636,

%U 12685512,11514069,2058000,85652,784,1,0,40320,27943920,357325100,522796680,156042999,12002256,252252,1296,1,0,362880,524580336,10941291000,24681106400,11453045625,1444332771,55566000,652500,2025,1

%N Triangle read by rows of products of (signless) Stirling numbers of the first kind (A132393) and Stirling numbers of the second kind (A008277).

%F Formula: a(n,k) = s(n,k)*S(n,k), where the s(n,k) are the (signless) Stirling numbers of the first kind and the S(n,k) are the Stirling numbers of the second kind.

%e Triangle begins:

%e 1

%e 0,1

%e 0,1,1

%e 0,2,9,1

%e 0,6,77,36,1

%e 0,24,750,875,100,1

%e 0,120,8494,20250,5525,225,1

%e 0,720,111132,488824,257250,24500,441,1

%e 0,5040,1659636,12685512,11514069,2058000,85652,784,1

%p seq(seq(abs(combinat[stirling1](n,k))*combinat[stirling2](n,k),k=0..n),n=0..8);

%t Flatten[Table[Table[Abs[StirlingS1[n, k]]*StirlingS2[n, k], {k, 0, n}],{n, 0, 8}] ,1]

%o (Maxima) create_list(abs(stirling1(n,k)*stirling2(n,k)),n,0,10,k,0,n);

%Y Cf. A132393, A008277

%K nonn,easy,tabl

%O 0,8

%A _Emanuele Munarini_, Mar 11 2011