|
%I #14 Feb 21 2019 23:18:02
%S 512,768,1152,1280,1408,1664,1728,1792,1920,2112,2176,2432,2496,2592,
%T 2688,2880,2944,3168,3200,3264,3520,3648,3712,3744,3872,3888,3968,
%U 4032,4160,4320,4416,4480,4576,4736,4752,4800,4896,4928,5248,5280,5408,5440
%N Composite numbers n such that juxtaposition of prime factors of n has length 9.
%C The last term is a(84018465) = 997210243 = 9973 * 99991. - _Giovanni Resta_, Mar 21 2013
%C Prime factors counted with multiplicity. - _Harvey P. Dale_, Jul 26 2017
%H Nathaniel Johnston, <a href="/A036333/b036333.txt">Table of n, a(n) for n = 1..10000</a>
%p isA036333 := 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))=9, n, NULL): end: seq(isA036333(n),n=2..5440); # _Nathaniel Johnston_, Jun 22 2011
%t jpf9Q[n_]:=CompositeQ[n]&&Total[IntegerLength[#[[1]]]#[[2]]&/@ FactorInteger[ n]]==9; Select[ Range[6000],jpf9Q] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jul 26 2017 *)
%Y Cf. A036326-A036334.
%K nonn,base,fini,easy
%O 1,1
%A _Patrick De Geest_, Dec 15 1998
|
