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A062171 Number of non-unitary divisors of n (A048105) > number of distinct prime divisors of n (A001221). 1

%I #8 Dec 15 2017 17:35:07

%S 8,16,24,27,32,36,40,48,54,56,60,64,72,80,81,84,88,90,96,100,104,108,

%T 112,120,125,126,128,132,135,136,140,144,150,152,156,160,162,168,176,

%U 180,184,189,192,196,198,200,204,208,216,220,224,225,228,232,234,240

%N Number of non-unitary divisors of n (A048105) > number of distinct prime divisors of n (A001221).

%H Charles R Greathouse IV, <a href="/A062171/b062171.txt">Table of n, a(n) for n = 1..10000</a>

%o (PARI) nud(n) = numdiv(n)-2^omega(n); j=[]; for(n=1,500, if(nud(n)>omega(n),j=concat(j,n))); j

%o (PARI) is(n)=my(f=factor(n)[,2]); prod(i=1,#f,f[i]+1)>2^#f+#f \\ _Charles R Greathouse IV_, Sep 18 2015

%Y Cf. A048105, A001221, A048108.

%K easy,nonn

%O 1,1

%A _Jason Earls_, Aug 28 2001

%E Offset corrected by _Charles R Greathouse IV_, Sep 18 2015

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Last modified August 23 06:45 EDT 2024. Contains 375375 sequences. (Running on oeis4.)