A077130 Smallest number which is relatively prime to all the numbers between n^2 and (n+1)^2, inclusive.

5, 11, 17, 13, 19, 17, 23, 29, 37, 31, 29, 43, 41, 47, 37, 59, 41, 53, 59, 79, 61, 53, 73, 71, 89, 61, 79, 71, 83, 89, 79, 73, 83, 103, 101, 107, 97, 103, 89, 113, 127, 103, 97, 107, 101, 131, 137, 127, 109, 131, 113, 149, 127, 179, 131, 149, 179, 167, 139, 149

Offset

1,1

Comments

Naturally every member is a prime.

Links

Table of n, a(n) for n=1..60.

Example

a(5) = 19 is the smallest number coprime to all the numbers from 25 to 36.

Prog

(PARI) for(k=1, 100, a=0:forprime(p=2, 10001, f=0:for(l=k*k, (k+1)^2, if(gcd(p, l)>1, f=1:break)): if(!f, a=p:break)): if(a, print1(a", "), print1("-, ")))

Crossrefs

Cf. A077128, A077129.

Sequence in context: A376332 A123082 A084037 * A119754 A239127 A220432

Adjacent sequences: A077127 A077128 A077129 * A077131 A077132 A077133

Keyword

nonn

Author

Amarnath Murthy, Oct 29 2002

Extensions

Corrected and extended by Ralf Stephan, Mar 19 2003

Status

approved