A101163 Diagonal sums of a Chebyshev number triangle.

1, 2, 3, 5, 10, 24, 64, 182, 542, 1685, 5473, 18594, 66063, 245078, 947057, 3802469, 15826392, 68158314, 303273906, 1392503108, 6590530876, 32117814629, 160998508095, 829301391150, 4385370872477, 23786062734932, 132224164567459

Offset

0,2

Comments

Diagonal sums of number triangle A101161.

Links

Table of n, a(n) for n=0..26.

Formula

a(n)=sum{k=0..floor(n/2), if(k=n-k, 1, 2T(n-2k, (k+2)/2)) where T(n, k)=(n/2)sum{j=0..floor(n/2), C(n-j, j)(-1)^j*(2k)^(n-2j)}.

Crossrefs

Cf. A101162.

Sequence in context: A063253 A099967 A106531 * A155587 A125658 A001200

Adjacent sequences: A101160 A101161 A101162 * A101164 A101165 A101166

Keyword

easy,nonn

Author

Paul Barry, Dec 03 2004

Status

approved