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A062876
Numbers of lattice points corresponding to incrementally largest circle radii in A062875.
2
4, 12, 20, 28, 44, 52, 68, 76, 92, 116, 124, 148, 164, 172, 188, 212, 236, 244, 268, 284, 292, 316, 332, 356, 388, 404, 412, 428, 436, 452, 508, 524, 548, 556, 596, 604, 628, 652, 668, 692, 716, 724, 764, 772, 788, 796, 844, 892, 908, 916, 932, 956, 964
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
Eric Weisstein's World of Mathematics, Circle Lattice Points
FORMULA
a(n) = A017113(A111333(n)-1) = 8*A111333(n) - 4.
For n >= 2 a(n) = 4*A000040(n) (a term in A013929). - David James Sycamore, Jun 15 2024
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
EXTENSIONS
Edited and extended by Ray Chandler, Jan 05 2012
STATUS
approved