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%I #26 Oct 28 2019 16:19:19
%S 1,6,36,54,120,2470,2640,3144,3780,32640,41280,52632,67184,1098176,
%T 1157904,2147450880
%N Indices of perfect polynomials over GF(2).
%C Numbers k such that k = A178908(k); sum of divisors of k-th GF(2) polynomial is the polynomial itself.
%C a(17) > 5*10^9. - _Amiram Eldar_, Oct 28 2019
%o (PARI) isok(n) = my(s = vecsum(divisors(Mod(1,2)*Pol(binary(n))))); subst(lift(s), x, 2) == n; \\ _Michel Marcus_, Jan 13 2019
%Y Cf. A178908, A091220, A000396, A178911.
%K nonn,more
%O 1,2
%A _Franklin T. Adams-Watters_, Jun 22 2010
%E a(14)-a(15) from _Amiram Eldar_, Jan 13 2019
%E a(16) from _Amiram Eldar_, Oct 28 2019