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A048839 Numbers n dividing P(n)!, where P(n) is the largest prime factor of n. 1
2, 3, 5, 6, 7, 10, 11, 13, 14, 15, 17, 19, 20, 21, 22, 23, 26, 28, 29, 30, 31, 33, 34, 35, 37, 38, 39, 40, 41, 42, 43, 44, 46, 47, 51, 52, 53, 55, 56, 57, 58, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 70, 71, 73, 74, 76, 77, 78, 79, 82, 83, 84, 85, 86, 87, 88, 89, 91, 92, 93, 94 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Solutions to Diophantine equation P(n)=K(n), where P(n) is the largest prime which divides n and K(n) is the Kempner function A002034.

REFERENCES

P. Erdős, C. Ashbacher, Thoughts of Pal Erdos on Some Smarandache Notions, Smarandache Notions Journal, Vol. 8, No. 1-2-3, 1997, 220-224.

LINKS

Table of n, a(n) for n=1..71.

FORMULA

a(n) ~ n. - Charles R Greathouse IV, Sep 20 2012

PROG

(PARI) is(n)=my(s=factor(n)[, 1]); s[#s]!%n==0 \\ Charles R Greathouse IV, Sep 20 2012

CROSSREFS

Complement is A057109.

Sequence in context: A203076 A247180 A317091 * A122144 A064052 A248792

Adjacent sequences:  A048836 A048837 A048838 * A048840 A048841 A048842

KEYWORD

nonn,easy

AUTHOR

Charles T. Le (charlestle(AT)yahoo.com)

EXTENSIONS

Corrected and extended by Naohiro Nomoto, Jul 14 2001

STATUS

approved

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Last modified December 16 04:22 EST 2019. Contains 330013 sequences. (Running on oeis4.)