A062532 Odd nonprimes squared, or A014076(n)^2.

1, 81, 225, 441, 625, 729, 1089, 1225, 1521, 2025, 2401, 2601, 3025, 3249, 3969, 4225, 4761, 5625, 5929, 6561, 7225, 7569, 8281, 8649, 9025, 9801, 11025, 12321, 13225, 13689, 14161, 14641, 15129, 15625, 16641, 17689, 18225, 19881, 20449

Offset: 1

Author

Jason Earls, Jul 10 2001

Keywords

• easy
• nonn

Links

• Harry J. Smith, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A014076.

Programs

Mathematica

With[{nn=500},Complement[Range[1,nn,2],Prime[Range[PrimePi[nn]]]]^2] (* Harvey P. Dale, Nov 12 2012 *)

PARI

je=[]; forstep(n=1,301,2, if(isprime(n), n+1,je=concat(je,n^2))); je

PARI

{ n=0; forstep (m=1, 10^9, 2, if(!isprime(m), write("b062532.txt", n++, " ", m^2); if (n==1000, break)) ) } \\ Harry J. Smith, Aug 08 2009

Python

from sympy import primepi
def A062532(n):
    if n == 1: return 1
    m, k = n-1, primepi(n) + n - 1 + (n>>1)
    while m != k:
        m, k = k, primepi(k) + n - 1 + (k>>1)
    return m**2 # Chai Wah Wu, Jul 31 2024