OFFSET
1,3
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
MATHEMATICA
A023531[n_] := SquaresR[1, 8n+9]/2;
a[n_]:= a[n]= Sum[A023531[j]*Floor[(n-j+1)*GoldenRatio^2], {j, Floor[(n+1)/2]}];
Table[a[n], {n, 80}] (* G. C. Greubel, Jan 28 2022 *)
PROG
(Magma)
A023531:= func< n | IsIntegral( (Sqrt(8*n+9) -3)/2 ) select 1 else 0 >;
[A024325(n) : n in [1..80]]; // G. C. Greubel, Jan 28 2022
(Sage)
def A023531(n):
if ((sqrt(8*n+9) -3)/2).is_integer(): return 1
else: return 0
[A023325(n) for n in (1..80)] # G. C. Greubel, Jan 28 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved