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Semiludic numbers or "Ludic semiprimes": numbers n for which A302037(n) = 2.
5

%I #9 Apr 06 2018 10:16:22

%S 4,6,9,10,14,15,19,22,26,27,31,34,35,39,46,50,55,58,59,63,65,73,74,75,

%T 82,86,94,95,99,101,103,106,113,122,133,134,135,142,145,147,154,155,

%U 163,166,167,171,178,182,185,187,194,203,205,214,219,230,238,242,243,245,253,254,255,262,263,269,271,279,286,293,298,299,311

%N Semiludic numbers or "Ludic semiprimes": numbers n for which A302037(n) = 2.

%C An analog for A001358 based on the Ludic factorization (see A302032).

%H Antti Karttunen, <a href="/A302038/b302038.txt">Table of n, a(n) for n = 1..3953</a>

%H <a href="/index/Si#sieve">Index entries for sequences generated by sieves</a>

%o (PARI) k=0; for(n=1,512,if(2==A302037(n),k++;print1(n,","))); \\ Other code as in A302037.

%Y Cf. A003309, A255127, A302032, A302037.

%Y Cf. A254100 (a subsequence).

%Y Cf. also A001358, A302036.

%K nonn

%O 1,1

%A _Antti Karttunen_, Apr 01 2018