A105626 -id:A105626 - cp's OEIS frontend

A105627 Column 1 of triangle A105626.

1, 6, 48, 480, 5736, 79584, 1256808, 22262640, 437315016, 9438589824, 222109617288, 5661445534800, 155427839133096, 4573268363775264, 143592923776842408, 4792636497324986160, 169456698405536983176

Offset: 0

Paul D. Hanna, Apr 16 2005

nonn

A105626 equals the cube of the matrix square-root of triangle A105615.

Cf. A105615, A105626.

{a(n)=local(R,M=matrix(n+2,n+2,m,j,if(m>=j,if(m==j,1,if(m==j+1,-2*j, polcoeff(1/sum(i=0,m-j,(2*i)!/i!/2^i*x^i)+O(x^m),m-j)))))^-3); R=(M+M^0)/2;for(i=1,floor(2*log(n+2)),R=(R+M*R^(-1))/2); return(if(n<0,0,R[n+2,2]))}

A105628 Row sums of triangle A105626.

Original entry on oeis.org

1, 4, 25, 208, 2152, 26524, 378700, 6142948, 111593932, 2244992404, 49561796380, 1191625266388, 31001841211852, 867899276874964, 26017959787456060, 831650920910208628, 28237504357447540972, 1014987937635390612724

Offset: 0

Paul D. Hanna, Apr 16 2005

nonn

A105626 equals the cube of the matrix square-root of triangle A105615.

Cf. A105615, A105626.

{a(n)=local(R,M=matrix(n+3,n+3,m,j,if(m>=j,if(m==j,1,if(m==j+1,-2*j, polcoeff(1/sum(i=0,m-j,(2*i)!/i!/2^i*x^i)+O(x^m),m-j)))))^-3); R=(M+M^0)/2;for(i=1,floor(2*log(n+2)),R=(R+M*R^(-1))/2); return(if(n<0,0,sum(k=0,n,R[n+1,k+1])))}

cp's OEIS Frontend

A105627 Column 1 of triangle A105626.

Views

Author

Keywords

Comments

Crossrefs

Programs

PARI