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Composite numbers n such that juxtaposition of prime factors of n has length 8.
1

%I #7 Feb 21 2019 23:17:42

%S 256,384,576,640,704,832,864,896,960,1056,1088,1216,1248,1296,1344,

%T 1440,1472,1584,1600,1632,1760,1824,1856,1872,1936,1944,1984,2016,

%U 2080,2160,2208,2240,2288,2368,2376,2400,2448,2464,2624,2640,2704,2720,2736

%N Composite numbers n such that juxtaposition of prime factors of n has length 8.

%C The last term of this sequence is a(8779116)=99691027.

%H Nathaniel Johnston, <a href="/A036332/b036332.txt">Table of n, a(n) for n = 1..10000</a>

%p isA036332 := 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))=8, n, NULL): end: seq(isA036332(n),n=2..2736); # _Nathaniel Johnston_, Jun 22 2011

%Y Cf. A036326-A036334.

%K nonn,base,fini,easy

%O 1,1

%A _Patrick De Geest_, Dec 15 1998