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%I #36 Jul 14 2016 08:39:52
%S 2,2,2,17,71,107,503,881,1103,1301,9521,15671,19543,31387,155849,
%T 360289,370061,492067,1349147,1356869,2010553,4652239,17051297,
%U 20831119,47326519,122164649,189695483,191912659
%N a(n) = largest Ramanujan prime R_k in A104272 that is <= A002386(n).
%C While many values in A214757(n) are equal to A000101(n), here it seems the only value such that A002386(n) is equal to a(n) is a(1) = R_k = A002386(1) = 2.
%C See "Let rho(m) = A179196(m)" comment at A001223.
%H Dana Jacobsen, <a href="/A214756/b214756.txt">Table of n, a(n) for n = 1..59</a>
%e A104272(94) = 1301 < 1327 = A002386(10), so a(10) = 1301.
%o (Perl) use ntheory ":all"; sub a_from_2386 { my $n = shift; $n = prev_prime($n) while !is_ramanujan_prime($n); $n } # _Dana Jacobsen_, Jul 13 2016
%o (Perl) perl -Mntheory=:all -nE 'my $n=$1 if /(\d+)$/; $r=ramanujan_primes($n>1e6 ? $n-1e6 : 2, $n); say ++$x," ",$r->[-1];' b002386.txt # _Dana Jacobsen_, Jul 13 2016
%Y Cf. A002386, A104272, A001223.
%Y Cf. A214925, A214926, A214757, A214924.
%K nonn
%O 1,1
%A _John W. Nicholson_, Jul 27 2012
%E Edited by _N. J. A. Sloane_, Aug 06 2012
%E a(16)-a(28) from _Donovan Johnson_, Nov 04 2012
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