OFFSET
1,1
COMMENTS
A088904(a(n)) = 1.
All terms > 2 are odd. - Robert Israel, Dec 05 2019
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
filter:= proc(n) local F, t, d, s, r, b;
F:= ifactors(n-1)[2];
d:= igcd(seq(t[2], t=F));
if d > 1 then return false fi;
for s in numtheory:-divisors(n) minus {1, n} do
r:= n/s-1;
F:= ifactors(s)[2];
d:= igcd(seq(t[2], t=F));
b:= mul(t[1]^(t[2]/d), t=F);
if r = b^padic:-ordp(r, b) then return false fi
od;
true
end proc:
select(filter, [2, seq(i, i=3..1000, 2)]); # Robert Israel, Dec 05 2019
MATHEMATICA
M = 200;
V = 2 - Mod[Range[M], 2];
For[x = 2, 1 + x^2 <= M, x++, For[i = 0, 2 x^i <= M, i++, For[j = Max[2, i], True, j++, t = x^i + x^j; If[t > M, Break[]]; V[[t]]++]]];
V[[1]] = 0; V[[2]] = 1;
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Oct 21 2003
EXTENSIONS
Entry completely revised: Hugo Pfoertner and Reinhard Zumkeller, Oct 20 2004
STATUS
approved