1,1

Inspired by the weaker Legendre conjecture that there should be at least one prime between n^2 and (n+1)^2.

T. D. Noe, Table of n, a(n) for n = 1..10000

a(10) = 2 because between 10*(10+1)/2=55 and (10+1)*(10+2)/2=66 there are 2 primes: 59, 61.

Table[ PrimePi[n(n + 1)/2] - PrimePi[n(n - 1)/2], {n, 2, 96}]

A000217, A014085, A065383, A065384.

Essentially the same as A066888 and A090970.

Sequence in context: A242062 A025848 A268197 * A066888 A029313 A144001

Adjacent sequences: A065379 A065380 A065381 * A065383 A065384 A065385

nonn

Reinhard Zumkeller, Nov 05 2001

Definition improved by Robert G. Wilson v, Apr 22 2003

approved