A075064 Smallest composite number == 1 mod first n prime numbers.

9, 25, 91, 841, 6931, 30031, 510511, 9699691, 223092871, 6469693231, 601681470391, 7420738134811, 304250263527211, 13082761331670031, 614889782588491411, 32589158477190044731, 1922760350154212639071

Offset

1,1

Links

Table of n, a(n) for n=1..17.

Example

a(5) = 6931 is the smallest composite number c such that c-1= 6930 is divisible by 2310, the product of first 5 prime numbers 2,3,5,7 and 11.

Prog

(PARI) g(n) = prod(i=1, n, prime(i)); k(n) = m=1; while(isprime(m*g(n)+1), m=m+1); print(m*g(n)+1); for(i=1, 30, k(i))

Crossrefs

Cf. A075063.

Sequence in context: A147436 A189118 A075067 * A147332 A147460 A147475

Adjacent sequences: A075061 A075062 A075063 * A075065 A075066 A075067

Keyword

nonn

Author

Amarnath Murthy, Sep 08 2002

Extensions

More terms from Matthew Conroy, Sep 10 2002

Status

approved