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%I #19 Jul 11 2019 15:18:23
%S 1,2,3,4,6,7,9,10,12,15,16,19,21,22,24,27,30,31,34,36,37,40,42,45,49,
%T 51,52,54,55,57,64,66,69,70,75,76,79,82,84,87,90,91,96,97,99,100,106,
%U 112,114,115,117,120,121,126,129,132,135,136,139,141,142,147,154,156,157
%N Number of odd numbers <= n-th prime.
%C This is A006254 (numbers n such that 2n-1 is prime) with a leading 1. - Lambert Klasen (lambert.klasen(AT)gmx.net), Nov 06 2005
%C Same as smallest k such that prime(n) divides C(2k,k). - _Jonathan Sondow_, Jan 20 2016
%C Positions of records in A046112. - _Hugo Pfoertner_, Jul 11 2019
%H Ray Chandler, <a href="/A111333/b111333.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = ceiling((prime_n)/2). - _Robert G. Wilson v_, Nov 07 2005
%p seq(ceil(ithprime(i)/2), i=1..100); # _Robert Israel_, Jan 20 2016
%t Table[ Ceiling[ Prime[n]/2], {n, 65}] (* _Robert G. Wilson v_ *)
%o (PARI) a(n)=(prime(n)+1)\2 \\ _Charles R Greathouse IV_, Sep 16 2015
%Y Cf. A006254, A046112, A049990, A062875.
%K nonn,easy
%O 1,2
%A _Giovanni Teofilatto_, Nov 05 2005
%E More terms from _Robert G. Wilson v_, Nov 07 2005
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