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A100486
a(n) = pi(n) + prime(n).
4
2, 4, 7, 9, 14, 16, 21, 23, 27, 33, 36, 42, 47, 49, 53, 59, 66, 68, 75, 79, 81, 87, 92, 98, 106, 110, 112, 116, 119, 123, 138, 142, 148, 150, 160, 162, 169, 175, 179, 185, 192, 194, 205, 207, 211, 213, 226, 238, 242, 244, 248, 254, 257, 267, 273, 279, 285, 287
OFFSET
1,1
LINKS
FORMULA
a(n) = A000720(n) + A000040(n). - Wesley Ivan Hurt, Jan 28 2014
EXAMPLE
a(21) = pi(21) + prime(21) = 8 + 73 = 81.
MAPLE
with(numtheory); A100486:=n->pi(n) + ithprime(n); seq(A100486(n), n=1..60); # Wesley Ivan Hurt, Jan 28 2014
MATHEMATICA
Table[PrimePi[n] + Prime[n], {n, 60}]
PROG
(PARI) a(n) = primepi(n) + prime(n); \\ Michel Marcus, Feb 24 2023
(Magma) [#PrimesUpTo(n) + NthPrime(n): n in [1..80]]; // G. C. Greubel, Apr 04 2023
(SageMath) [prime_pi(n) + nth_prime(n) for n in range(1, 81)] # G. C. Greubel, Apr 04 2023
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Nov 22 2004
STATUS
approved