OFFSET
0,5
FORMULA
PROG
(PARI) a(n) = my(c=0, r); while(n, [n, r]=divrem(n, 3); if(r==2, return(0)); c+=r); c!; \\ Kevin Ryde, Nov 14 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Nov 11 2020
STATUS
approved