A113102 Column 1 of triangle A113101.

1, 20, 894, 108292, 39188597, 45157269264, 172969059719500, 2268555493366383236, 104065414379018585400528, 16965802042440759287849083708, 9953305892540385313201626908460431

Offset: 1

Author

Paul D. Hanna, Oct 14 2005

Keywords

• nonn

Crossrefs

Cf. A113101.

Programs

PARI

{a(n)=local(M=matrix(n+1,n+1));for(r=1,n+1, for(c=1,r, M[r,c]=if(r==c,1,if(c>1,(M^4)[r-1,c-1])+(M^4)[r-1,c]))); return(if(n<1,0,(M^4)[n+1,2]))}

Extensions

Offset changed to 1 by Georg Fischer, Jun 20 2022