A110204 a(n) = sum of squares of numbers < 2^n having exactly 4 ones in their binary representation.

0, 0, 0, 225, 3224, 29274, 215900, 1412275, 8541876, 48876212, 268288008, 1425694725, 7381073920, 37399844174, 186110137668, 911952794935, 4409472232060, 21073909951080, 99688911645264, 467292120940425

Offset

1,4

Comments

Equals column 4 of triangle A110200.

Links

Table of n, a(n) for n=1..20.

Formula

G.f.: x^4*(225-2626*x+12500*x^2-30872*x^3+41536*x^4-28928*x^5+8192*x^6)/ ((1-x)^4*(1-2*x)^3*(1-4*x)^4).

Prog

(PARI) {a(n)=polcoeff(x^4*(225-2626*x+12500*x^2-30872*x^3+41536*x^4-28928*x^5+8192*x^6)/ ((1-x)^4*(1-2*x)^3*(1-4*x)^4+x*O(x^n)), n)}

Crossrefs

Cf. A110200 (triangle), A110201 (central terms), A002450 (column 1), A110202 (column 2), A110203 (column 3).

Sequence in context: A184878 A134741 A379121 * A180697 A230065 A218813

Adjacent sequences: A110201 A110202 A110203 * A110205 A110206 A110207

Keyword

nonn

Author

Paul D. Hanna, Jul 16 2005

Status

approved