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A032786 Numbers k such that k(k+1)(k+2)...(k+15) / (k+(k+1)+(k+2)+...+(k+15)) is an integer. 1
0, 3, 5, 6, 9, 10, 12, 15, 17, 20, 24, 25, 30, 31, 33, 38, 42, 45, 51, 53, 55, 60, 64, 66, 75, 77, 80, 87, 90, 105, 108, 114, 115, 129, 130, 141, 150, 155, 168, 174, 180, 185, 195, 207, 213, 220, 240, 246, 255, 262, 276, 285, 295, 305, 311, 330, 339, 350, 357 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
(d-15)/2 where d >= 15 divides 4108830350625. In particular, the sequence is finite. - Robert Israel, Jul 13 2018
LINKS
MAPLE
sort([seq((t-15)/2, t=select(`>=`, numtheory:-divisors(4108830350625), 15))]); # Robert Israel, Jul 13 2018
MATHEMATICA
Select[Range[0, 500], IntegerQ[Times@@Range[#, #+15]/Total[Range[ #, #+15]]]&] (* Harvey P. Dale, Sep 02 2016 *)
CROSSREFS
Sequence in context: A080307 A001969 A075311 * A080309 A281746 A287162
KEYWORD
nonn,fini,full
AUTHOR
Patrick De Geest, May 15 1998
EXTENSIONS
Definition corrected by Harvey P. Dale, Sep 02 2016
Offset changed by Robert Israel, Jul 13 2018
STATUS
approved

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Last modified April 25 11:03 EDT 2024. Contains 371967 sequences. (Running on oeis4.)