login
A163620
Let q(p) be the smallest prime greater than the prime p. a(n) is the smallest integer > n that is divisible by each q(p) for all primes p dividing n.
1
3, 5, 6, 7, 15, 11, 9, 10, 21, 13, 15, 17, 33, 35, 18, 19, 30, 23, 21, 55, 39, 29, 30, 28, 51, 30, 33, 31, 105, 37, 33, 65, 57, 77, 45, 41, 69, 85, 42, 43, 165, 47, 78, 70, 87, 53, 60, 55, 63, 95, 102, 59, 60, 91, 66, 115, 93, 61, 105, 67, 111, 110, 66, 119, 195, 71, 114, 145
OFFSET
2,1
LINKS
EXAMPLE
18 is divisible by 2 and 3. q(2) = 3, and q(3) = 5. So a(18) is the smallest integer > 18 that is divisible by both 3 and 5. Therefore a(18) = 30.
MATHEMATICA
spf[n_]:=Module[{prs=NextPrime/@FactorInteger[n][[All, 1]], p, k=1}, p= LCM@@ prs; While[ k*p<n, k++]; k*p]; Array[spf, 70, 2]
CROSSREFS
Sequence in context: A006754 A281725 A274928 * A227722 A250419 A072134
KEYWORD
nonn
AUTHOR
Leroy Quet, Aug 01 2009
EXTENSIONS
Correct second term and extend sequence Sean A. Irvine, Sep 06 2009
STATUS
approved