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A135716
Numbers n such that all numbers of the form p(n)#/p(k) +- 1, where 1 <= k <= n, are composite.
2
119, 144, 210, 245, 260, 285, 317, 352
OFFSET
1,1
COMMENTS
p(k) is k-th prime; p(n)# is n-th primorial, A002110(n). No more terms <= 500.
FORMULA
Numbers n such that A135714(n)+A135715(n)=0.
EXAMPLE
119 is a term as p(119)#/p(k)+1 is composite for all 1 <= k <= 119 and p(119)#/p(k)-1 is likewise composite for the same k values; there are 238 such composite numbers.
PROG
(PARI)
CROSSREFS
KEYWORD
nonn
AUTHOR
Rick L. Shepherd, Nov 30 2007
STATUS
approved