OFFSET
0,2
MATHEMATICA
Join[{1}, Table[ 24*Sum[ d*Mod[d, 2], {d, Divisors[n]}], {n, 1, 10^6}]] // Accumulate // Select[#, IntegerQ[Sqrt[#]] &] & (* Jean-François Alcover, Jul 02 2013 *)
PROG
(PARI) B=1; print1(B, ", "); for (n=1, 200000, t1=divisors(2*n); t2=0; for (i=1, length(t1), if( t1[ i ]%4 <> 0, t2=t2+t1[ i ])); B=B+8*t2; if (issquare(B), print1(B, ", ")))
CROSSREFS
KEYWORD
nonn,nice,more
AUTHOR
EXTENSIONS
a(17)-a(18) from Jason Earls, Jul 21 2001
a(19)-a(21) from Sean A. Irvine, May 07 2021
STATUS
approved