OFFSET
0,4
COMMENTS
Leading zeros are ignored.
LINKS
Rémy Sigrist, Table of n, a(n) for n = 0..6561
FORMULA
a(n) = 0 iff n is a palindrome in base 3 (A014190).
MAPLE
a:= n-> (l-> (h-> add(h[j]*3^(j-1), j=1..nops(h)))([seq(
abs(l[i]-l[-i]), i=1..nops(l))]))(convert(n, base, 3)):
seq(a(n), n=0..70); # Alois P. Heinz, Nov 12 2020
PROG
(PARI) a(n, base=3) = my (d=digits(n, base)); fromdigits(abs(d-Vecrev(d)), base)
CROSSREFS
KEYWORD
AUTHOR
Rémy Sigrist, Nov 11 2020
STATUS
approved