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A178909
Indices of perfect polynomials over GF(2).
2
1, 6, 36, 54, 120, 2470, 2640, 3144, 3780, 32640, 41280, 52632, 67184, 1098176, 1157904, 2147450880
OFFSET
1,2
COMMENTS
Numbers k such that k = A178908(k); sum of divisors of k-th GF(2) polynomial is the polynomial itself.
a(17) > 5*10^9. - Amiram Eldar, Oct 28 2019
PROG
(PARI) isok(n) = my(s = vecsum(divisors(Mod(1, 2)*Pol(binary(n))))); subst(lift(s), x, 2) == n; \\ Michel Marcus, Jan 13 2019
CROSSREFS
KEYWORD
nonn,more
AUTHOR
EXTENSIONS
a(14)-a(15) from Amiram Eldar, Jan 13 2019
a(16) from Amiram Eldar, Oct 28 2019
STATUS
approved