A089617 Number of primes between n^2 and (n+1/7)^2.

0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 2, 2, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 2, 1, 1, 0, 1, 1, 2, 3, 1, 2, 3, 1, 3, 2, 3, 0, 0, 1, 0, 2, 1, 2, 2, 1, 1, 1, 3, 1, 2, 1, 1, 4, 2, 1, 3, 2, 3, 0, 2, 4, 3, 2, 3, 0, 3, 2, 2, 2, 3, 2, 3, 1, 3, 3, 1, 5, 2, 3, 3, 4, 2, 5, 3, 3, 4, 4, 1, 2, 4, 4, 4, 5, 5, 4, 2, 2, 3, 3, 2, 2

Offset

1,14

Links

Table of n, a(n) for n=1..105.

Mathematica

Table[PrimePi[(n+1/7)^2]-PrimePi[n^2], {n, 110}] (* Harvey P. Dale, Dec 04 2020 *)

Prog

(PARI) pbetweensq2(n) = { for(x=1, n, c=0; for(y=floor(x)^2, (x+1/7)^2, if(isprime(y), c++) ); print1(c", ") ) }

Crossrefs

Sequence in context: A046751 A124478 A030353 * A359217 A359216 A274370

Adjacent sequences: A089614 A089615 A089616 * A089618 A089619 A089620

Keyword

easy,nonn

Author

Cino Hilliard, Dec 31 2003

Status

approved