OFFSET
0,3
EXAMPLE
a(7)=2 as we have 7+0=5+2
PROG
(PARI) { v=vector(101); v[1]=0; for (i=1, 50, v[2*i]=i*(3*i-1)/2; v[2*i+1]=i*(3*i+1)/2); x=vector(500); for (a=1, 50, for (b=a, 50, if (v[a]+v[b]<500, x[v[a]+v[b]+1]++))); x }
CROSSREFS
KEYWORD
nonn
AUTHOR
Jon Perry, Mar 29 2004
STATUS
approved