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%I #9 Dec 24 2023 02:42:04
%S 1,2,3,4,7,8,11,12,16,17,18,19,27,28,31,43,44,47,48,49,52,63,67,75,79,
%T 80,97,98,112,116,124,127,147,148,162,163,171,172,175,191,192,207,211,
%U 241,242,243,244,256,268,271,283,288,292,316,324,331,332,337,367
%N Numbers k such that k and k+1 are both in A268375.
%C Analogous to A342028, as A268375 is analogous to A130091.
%C The Mersenne primes (A000668) are terms.
%H Amiram Eldar, <a href="/A368402/b368402.txt">Table of n, a(n) for n = 1..10000</a>
%t f[e_] := Position[Reverse[IntegerDigits[e, 2]], 1] // Flatten; q[n_] := q[n] = UnsameQ @@ Flatten[f /@ FactorInteger[n][[;; , 2]]]; Select[Range[100], q[#] && q[#+1] &]
%o (PARI) isA268375(n) = {my(e = factor(n)[,2], b = 0); for(i=1, #e, b = bitor(b, e[i])); n == 1 || b == vecsum(e);}
%o lista(kmax) = {my(is1 = 0, is2); for(k = 1, kmax, is2 = isA268375(k); if(is1 && is2, print1(k-1, ", ")); is1 = is2);}
%Y Subsequence of A130091, A268375 and A342028.
%Y Subsequences: A000668, A368403, A368404.
%K nonn,base
%O 1,2
%A _Amiram Eldar_, Dec 23 2023