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A164798 a(n) = the smallest integer >= n such that a(n)!/(n-1)! is divisible by every prime from 2 to the largest prime divisor of a(n)!/(n-1)!. (a(1)=1.) 3
1, 2, 4, 4, 6, 6, 10, 8, 10, 14, 15, 12, 22, 15, 16, 16, 26, 18, 34, 21, 38, 38, 38, 24, 46, 46, 46, 46, 46, 30, 58, 32, 62, 62, 36, 36, 62, 74, 74, 74, 74, 82, 82, 86, 86, 86, 86, 48, 94, 94, 94, 94, 94, 54, 106, 106, 106, 106, 106, 60, 118, 122, 66, 64, 122, 122, 122, 134 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) = A164799(n) + n -1.

LINKS

Table of n, a(n) for n=1..68.

EXAMPLE

Consider the products of consecutive integers, m!/9!, m >= 10. First, 10 is divisible by 2 and 5, but there is a prime gap since 3 is missing from the factorization. 10*11 is divisible by 2, 5, and 11, but 3 and 7 are missing. 10*11*12 is divisible by 2, 3, 5, and 11, but 7 is missing. 10*11*12*13 is divisible by all primes up to 13, except 7. But 10*11*12*13*14 is indeed divisible by every prime from 2 to 13. So a(10) = 14.

CROSSREFS

Cf. A164799

Sequence in context: A111457 A161765 A232091 * A087554 A281072 A226951

Adjacent sequences:  A164795 A164796 A164797 * A164799 A164800 A164801

KEYWORD

nonn

AUTHOR

Leroy Quet, Aug 26 2009

EXTENSIONS

Terms beyond a(13) from R. J. Mathar, Feb 27 2010

STATUS

approved

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Last modified April 19 06:30 EDT 2019. Contains 322237 sequences. (Running on oeis4.)