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Numbers k such that k(k+1)(k+2)...(k+17) / (k+(k+1)+(k+2)+ ... +(k+17)) is an integer.
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%I #18 Jul 13 2018 21:04:32

%S 0,2,4,5,8,9,11,14,16,17,19,23,24,29,30,32,34,37,41,44,50,51,52,54,59,

%T 63,65,68,74,76,79,85,86,89,102,104,107,113,114,119,128,129,136,140,

%U 149,154,167,170,173,179,184,194,204,206,212,219,221,239,245,254

%N Numbers k such that k(k+1)(k+2)...(k+17) / (k+(k+1)+(k+2)+ ... +(k+17)) is an integer.

%C (d-17)/2 where d >= 17 divides 131939107925625. In particular, the sequence is finite. - _Robert Israel_, Jul 13 2018

%H Robert Israel, <a href="/A032787/b032787.txt">Table of n, a(n) for n = 1..2827</a>

%p sort([seq((t-17)/2, t=select(`>=`,numtheory:-divisors(131939107925625),17))]); # _Robert Israel_, Jul 13 2018

%t Select[Range[0,300],IntegerQ[Times@@Range[#,#+17]/Total[Range[#,#+17]]]&] (* _Harvey P. Dale_, Sep 02 2016 *)

%Y Cf. A032765-A032798.

%K nonn,fini,full

%O 1,2

%A _Patrick De Geest_, May 15 1998

%E Definition corrected by _Harvey P. Dale_, Sep 02 2016