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A335882 Numbers k for which A331410(k) = 2.

%I A335882 #16 Jan 09 2025 15:04:11
%S A335882 5,9,10,11,13,18,20,21,22,23,26,36,40,42,44,46,47,49,52,61,72,80,84,
%T A335882 88,92,93,94,98,104,122,144,160,168,176,184,186,188,191,196,208,217,
%U A335882 223,244,288,320,336,352,368,372,376,381,382,383,392,416,434,446,488,576,640,672,704,736,744,752,762,764,766,784,832,868,889,892,961
%N A335882 Numbers k for which A331410(k) = 2.
%C A335882 Numbers k such that A000265(k) is either in A144482 or in A335874.
%C A335882 Each term is either of the form A335874(n)*2^k, for some n >= 2, and k >= 0, or a product of two terms of A335431, whether distinct or not.
%H A335882 Antti Karttunen, <a href="/A335882/b335882.txt">Table of n, a(n) for n = 1..600</a>
%o A335882 (PARI)
%o A335882 A000265(n) = (n>>valuation(n,2));
%o A335882 isA000668(n) = (isprime(n)&&!bitand(n,1+n));
%o A335882 isA144482(n) = ((2==bigomega(n))&&isA000668(vecmin(factor(n)[,1]))&&isA000668(vecmax(factor(n)[,1])));
%o A335882 isA335874(n) = ((n>2)&&isprime(n)&&isA000668(A000265(1+n)));
%o A335882 isA335882(n) = (isA335874(A000265(n))||isA144482(A000265(n)));
%Y A335882 Row 2 of A335430.
%Y A335882 Cf. A331410, A335431, A335874 (after its initial 2, gives the primes in this sequence), A144482 (odd semiprimes in this sequence).
%Y A335882 Cf. also A334102.
%K A335882 nonn
%O A335882 1,1
%A A335882 _Antti Karttunen_, Jun 28 2020