A087417 Sum of the cubes of A058182.
-1, 0, 0, 1, 2, 10, 135, 19818, 395466722, 156401766357161409, 24461512581491800525933058683030176
Offset: 0
Keywords
Examples
A058182 begins 1,1,2,5,27,734,538783...=b(n) 1^3+1^3=2=a(2)=1*2=b(2)*b(3). 1^3+1^3+2^3=10=a(3)=2*5=b(3)*b(4). 1^3+1^3+2^3+5^3=135=a(4)=5*27=b(4)*b(5). 1^3+1^3+2^3+5^3+27^3=19818=a(5)=b(5)*b(6).
Crossrefs
Cf. A058182.
Programs
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PARI
{a(n) = local(a0, a1, a2); if( n<0, a(-n), if( n<3, -(n==0), a0 = a1 = 1; for(i=4, n, a2 = a1^2 + a0; a0 = a1; a1 = a2); a1*a0))}; /* Michael Somos, May 22 2005 */
Formula
a(n+1) = a(n) + A058182(n)^3, a(-n) = a(n) for all n in Z.
Comments