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A351552 Numbers k for which A351546(k) divides k, where A351546(n) is the largest unitary divisor of sigma(n) such that none of its prime factors divide A003961(n).

%I A351552 #13 Feb 17 2022 14:17:13
%S A351552 1,2,10,20,24,34,40,106,120,160,216,224,260,340,408,440,480,520,580,
%T A351552 672,680,696,792,820,1060,1120,1272,1392,1450,1640,1666,1760,1780,
%U A351552 1940,2080,2120,2136,2320,2340,2464,2720,2900,3040,3320,3332,3576,3680,3808,3880,3960,4280,4320,4536,4640,4680,5280,5380,5800,5860
%N A351552 Numbers k for which A351546(k) divides k, where A351546(n) is the largest unitary divisor of sigma(n) such that none of its prime factors divide A003961(n).
%C A351552 See comments in A351551.
%H A351552 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%H A351552 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%o A351552 (PARI)
%o A351552 A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
%o A351552 A351546(n) = { my(f=factor(sigma(n)),u=A003961(n)); prod(k=1,#f~,f[k,1]^((0!=(u%f[k,1]))*f[k,2])); };
%o A351552 isA351552(n) = !(n%A351546(n));
%Y A351552 Cf. A000203, A003961, A351546.
%Y A351552 Not a subsequence of A351554.
%Y A351552 Cf. A351551 (subsequence).
%K A351552 nonn
%O A351552 1,2
%A A351552 _Antti Karttunen_, Feb 16 2022