OFFSET
1,1
COMMENTS
For n = 1 and n >= 3, a(n) is the smallest nonsquarefree number divisible by prime(n). - David James Sycamore, Jun 15 2024
LINKS
Ray Chandler, Table of n, a(n) for n = 1..10000
Eric Weisstein's World of Mathematics, Circle Lattice Points
FORMULA
MATHEMATICA
Join[{4}, Table[4 Prime[n], {n, 2, 50}]] (* Vincenzo Librandi, May 08 2015 *)
PROG
(Magma) [4] cat [4*NthPrime(n): n in [2..60]]; // Vincenzo Librandi, May 08 2015
(PARI) a(n)=if(n>1, 4*prime(n), 4) \\ Charles R Greathouse IV, May 08 2015
(Python)
from sympy import prime
def A062876(n): return prime(n)<<2 if n>1 else 4 # Chai Wah Wu, Aug 02 2024
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
EXTENSIONS
Edited and extended by Ray Chandler, Jan 05 2012
STATUS
approved