

A214756


a(n) = largest Ramanujan prime R_k in A104272 that is <= A002386(n).


5



2, 2, 2, 17, 71, 107, 503, 881, 1103, 1301, 9521, 15671, 19543, 31387, 155849, 360289, 370061, 492067, 1349147, 1356869, 2010553, 4652239, 17051297, 20831119, 47326519, 122164649, 189695483, 191912659
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OFFSET

1,1


COMMENTS

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.
See "Let rho(m) = A179196(m)" comment at A001223.


LINKS

Dana Jacobsen, Table of n, a(n) for n = 1..59


EXAMPLE

A104272(94) = 1301 < 1327 = A002386(10), so a(10) = 1301.


PROG

(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
(Perl) perl Mntheory=:all nE 'my $n=$1 if /(\d+)$/; $r=ramanujan_primes($n>1e6 ? $n1e6 : 2, $n); say ++$x, " ", $r>[1]; ' b002386.txt # Dana Jacobsen, Jul 13 2016


CROSSREFS

Cf. A002386, A104272, A001223.
Cf. A214925, A214926, A214757, A214924.
Sequence in context: A098919 A161748 A195871 * A079007 A064215 A087238
Adjacent sequences: A214753 A214754 A214755 * A214757 A214758 A214759


KEYWORD

nonn


AUTHOR

John W. Nicholson, Jul 27 2012


EXTENSIONS

Edited by N. J. A. Sloane, Aug 06 2012
a(16)a(28) from Donovan Johnson, Nov 04 2012


STATUS

approved



