A337346 - OEIS

%I #8 Aug 27 2020 08:57:43

%S 0,0,0,0,0,0,0,1,0,0,0,2,0,0,0,2,0,2,0,2,0,0,0,4,0,0,1,2,0,3,0,3,0,0,

%T 0,5,0,0,0,4,0,3,0,1,2,0,0,6,0,1,0,1,0,4,0,4,0,0,0,7,0,0,2,4,0,1,0,1,

%U 0,3,0,8,0,0,1,1,0,2,0,6,2,0,0,7,0,0,0,3,0,7,0,1,0,0,0,8,0,2,1,4,0,1,0,3,3

%N Number of proper divisors d of n for which A003961(d) > 2*d.

%C Number of terms of A246282 less than n that divide n.

%C Number of proper divisors d of n for which A048673(d) > d.

%H Antti Karttunen, <a href="/A337346/b337346.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%F a(n) = Sum_{d|n, d<n} A252742(d).

%F a(n) = A337345(n) - A252742(n).

%o (PARI)

%o A003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };

%o A337346(n) = sumdiv(n,d,(d<n)&&(A003961(d)>(d+d)));

%Y Cf. A003961, A048673, A246282, A252742, A337345, A337372.

%Y Cf. also A294929.

%K nonn

%O 1,12

%A _Antti Karttunen_, Aug 27 2020