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.

A036327 Composite numbers n such that juxtaposition of prime factors of n has length 3.

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%I A036327 #11 Feb 21 2019 23:16:28
%S A036327 8,12,18,20,22,26,27,28,30,33,34,38,39,42,45,46,50,51,55,57,58,62,63,
%T A036327 65,69,70,74,75,77,82,85,86,87,91,93,94,95,98,105,106,111,115,118,119,
%U A036327 122,123,125,129,133,134,141,142,145,146,147,155,158,159,161,166,175
%N A036327 Composite numbers n such that juxtaposition of prime factors of n has length 3.
%C A036327 The last term is a(104)=679.
%H A036327 Nathaniel Johnston, <a href="/A036327/b036327.txt">Table of n, a(n) for n = 1..104</a> (full sequence)
%p A036327 isA036327 := proc(n) local d: d:=ifactors(n)[2]: return `if`(not isprime(n) and add(length(d[j][1])*d[j][2], j=1..nops(d))=3, n, NULL): end: seq(isA036327(n),n=2..999); # _Nathaniel Johnston_, Jun 22 2011
%Y A036327 Cf. A036326-A036334.
%K A036327 nonn,base,easy,fini,full
%O A036327 1,1
%A A036327 _Patrick De Geest_, Dec 15 1998