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A109652
a(n) = prime(A000201(n)).
2
2, 5, 7, 13, 19, 23, 31, 37, 43, 53, 59, 67, 73, 79, 89, 97, 103, 109, 113, 131, 137, 149, 157, 163, 173, 181, 191, 197, 199, 223, 229, 233, 241, 257, 263, 271, 277, 283, 307, 311, 317, 331, 347, 353, 359, 373, 383, 389, 401, 409, 421, 433, 439, 449, 457, 463
OFFSET
1,1
FORMULA
a(n) ~ phi*n*log n, where phi = (1+sqrt(5))/2. - Charles R Greathouse IV, Apr 19 2015
PROG
(PARI) a(n) = prime(n*(1+sqrt(5))\2); \\ Michel Marcus, Aug 28 2013
(Python)
from math import isqrt
from sympy import prime
def A109652(n): return prime(n+isqrt(5*n**2)>>1) # Chai Wah Wu, Aug 10 2022
CROSSREFS
KEYWORD
nonn,less
AUTHOR
E.J.P. Vening, Aug 05 2005
EXTENSIONS
Better description from Joseph Biberstine and Graeme McRae, Aug 05 2006
STATUS
approved