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A232634
Ramanujan primes of the form 3*k + 1.
1
67, 97, 127, 151, 181, 229, 241, 307, 349, 367, 373, 409, 433, 439, 487, 571, 601, 607, 643, 727, 739, 751, 769, 823, 853, 937, 967, 1009, 1021, 1051, 1063, 1087, 1249, 1297, 1423, 1429, 1447, 1489, 1549, 1567, 1579, 1597, 1609, 1663, 1693, 1777, 1783, 1789, 1861, 1867, 1987, 1999, 2083, 2131
OFFSET
1,1
COMMENTS
Ramanujan primes p such that tau(p) == 2 (mod 3) where tau(x) is the Ramanujan tau function (A000594).
Intersection of A002476 and A104272.
LINKS
PROG
(Perl) use ntheory ":all"; for $p (@{ramanujan_primes(1e6)}) { say ++$i, " $p" unless ($p-1) % 3 } # - Dana Jacobsen, Aug 13 2015
(Perl) use ntheory ":all"; for $p (@{ramanujan_primes(1e6)}) { say ++$i, " $p" if (ramanujan_tau($p) % 3) == 2; } # Much slower alternate method - Dana Jacobsen, Aug 13 2015
CROSSREFS
Sequence in context: A039539 A256176 A158848 * A302345 A276307 A260806
KEYWORD
nonn
AUTHOR
Irina Gerasimova, Nov 27 2013
EXTENSIONS
Corrected by Dana Jacobsen, Aug 13 2015.
STATUS
approved