A088526 a(n) = A061017(n) - pi(n) - 1.

0, 0, -1, 0, -1, 0, -1, -1, 0, 0, 0, 0, -1, -1, 0, 0, 0, 0, -1, -1, 0, 0, -1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 2, 2, 1, 1, 1, 1, 0, 0, 1, 1, 1, 2, 1, 1, 1, 2, 2, 2, 2, 3, 2, 2, 2, 2, 1, 2, 1, 2, 2

Offset

1,77

Comments

a(n) >= 0 for all n >= 24.

The old entry with this sequence number was a duplicate of A074292.

Links

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

Prog

(Python)
from math import isqrt
from sympy import primepi
from oeis_sequences.OEISsequences import bisection, bsearch
def A088526(n):
    def g(x): return x-(s:=isqrt(x))**2+(sum(x//k for k in range(1, s+1))<<1)
    def f(x): return n+bsearch(g, x)
    return bisection(f, n, n)-n-primepi(n) # Chai Wah Wu, Mar 01 2026

Crossrefs

Cf. A061017, A006218, A098357, A052511.

Sequence in context: A181059 A111915 A066520 * A334091 A054535 A054534

Adjacent sequences: A088523 A088524 A088525 * A088527 A088528 A088529

Keyword

sign

Author

David Applegate and N. J. A. Sloane, Oct 22 2008

Status

approved