A192563 a(n) = Sum_{k=0..n} abs(Stirling1(n+1,k+1))*Stirling2(n+1,k+1)*k!.

1, 2, 13, 161, 3148, 87784, 3274640, 156359874, 9252910816, 662065322016, 56172251821992, 5562573507747288, 634574662217269824, 82482896750780978880, 12101565966159294983808, 1987899464090970683668944, 363036441677797499946379776

Offset: 0

Author

Emanuele Munarini, Jul 04 2011

Keywords

• nonn

Links

• Stefano Spezia, Table of n, a(n) for n = 0..270

Crossrefs

Diagonal of the array A344639.

Cf. A000142, A008275, A008277, A081048.

Programs

Mathematica

Table[Sum[Abs[StirlingS1[n+1,k+1]]StirlingS2[n+1,k+1]k!,{k,0,n}],{n,0,100}]

Maxima

makelist(sum(abs(stirling1(n+1,k+1))*stirling2(n+1,k+1)*k!,k,0,n),n,0,12);