A061237 Prime numbers == 1 (mod 9).

19, 37, 73, 109, 127, 163, 181, 199, 271, 307, 379, 397, 433, 487, 523, 541, 577, 613, 631, 739, 757, 811, 829, 883, 919, 937, 991, 1009, 1063, 1117, 1153, 1171, 1279, 1297, 1423, 1459, 1531, 1549, 1567, 1621, 1657, 1693, 1747, 1783, 1801, 1873, 1999

Offset: 1

Author

Amarnath Murthy, Apr 23 2001

Keywords

• nonn
• easy

Links

• Harry J. Smith, Table of n, a(n) for n = 1..2000

Crossrefs

Cf. A010888, A061238, A061239, A061240, A061241, A061242.

Programs

Magma

[ p: p in PrimesUpTo(2000) | p mod 9 in {1} ]; // Vincenzo Librandi, Dec 25 2010

Mathematica

Select[ Range[ 2000 ], PrimeQ[ # ] && Mod[ #, 9 ] == 1 & ]
Select[Prime[Range[350]],Mod[#,9]==1&] (* Harvey P. Dale, Jan 06 2013 *)

PARI

isok(p) = { isprime(p) && p%9 == 1 } \\ Harry J. Smith, Jul 19 2009

Formula

A010888(a(n)) = 1. - Reinhard Zumkeller, Feb 25 2005

a(n) ~ 6n log n. - Charles R Greathouse IV, May 14 2025

Extensions

More terms from Robert G. Wilson v, May 10 2001