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A069148 Numbers n such that n*n!/A062758(n) is not an integer where A062758(n) is the product of squares of divisors of n. 1
4, 6, 8, 10, 14, 16, 18, 20, 22, 26, 28, 34, 38, 42, 44, 46, 52, 58, 62, 66, 68, 74, 76, 78, 82, 86, 92, 94, 102, 106, 114, 116, 118, 122, 124, 134, 138, 142, 146, 148, 158, 164, 166, 172, 174, 178, 186, 188, 194, 202, 206, 212, 214, 218, 222, 226, 236, 244, 246 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..59.

MATHEMATICA

Rest[Position[Table[(n*n!)/(Times@@Divisors[n])^2, {n, 250}], _?(!IntegerQ[ #]&)]//Flatten] (* Harvey P. Dale, Apr 24 2019 *)

PROG

(PARI) for(n=1, 320, if((n*(n!))%(n^numdiv(n))>0, print1(n, ", ")))

CROSSREFS

Complement of A069149.

Cf. A001563 (n*n!), A062758.

Sequence in context: A316262 A075124 A067315 * A328144 A103800 A022449

Adjacent sequences:  A069145 A069146 A069147 * A069149 A069150 A069151

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, Apr 08 2002

STATUS

approved

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Last modified December 8 04:31 EST 2019. Contains 329850 sequences. (Running on oeis4.)