cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A334146 Numbers with at least two prime factors greater than 3 counted with multiplicity.

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%I A334146 #17 Aug 16 2020 11:46:37
%S A334146 25,35,49,50,55,65,70,75,77,85,91,95,98,100,105,110,115,119,121,125,
%T A334146 130,133,140,143,145,147,150,154,155,161,165,169,170,175,182,185,187,
%U A334146 190,195,196,200,203,205,209,210,215,217,220,221,225,230,231,235,238,242
%N A334146 Numbers with at least two prime factors greater than 3 counted with multiplicity.
%F A334146 a(n) ~ n. - _Charles R Greathouse IV_, Apr 16 2020
%e A334146 25 = 5*5
%e A334146 35 = 5*7
%e A334146 49 = 7*7
%e A334146 50 = (2)*5*5
%e A334146 55 = 5*11
%e A334146 65 = 5*13
%e A334146 70 = (2)*5*7
%e A334146 75 = (3)*5*5
%t A334146 Select[Range[250], CompositeQ[# / 2^IntegerExponent[#, 2] / 3^IntegerExponent[#, 3]] &] (* _Amiram Eldar_, May 01 2020 *)
%o A334146 (PARI) is(n)=n>>=valuation(n,2);n/=3^valuation(n,3);n>1 && !isprime(n) \\ _Charles R Greathouse IV_, Apr 16 2020
%Y A334146 Cf. A093641.
%K A334146 nonn,easy
%O A334146 1,1
%A A334146 _Aidan Clarke_, Apr 16 2020