A158277 The lesser of twin prime pairs with each prime in a different century.

599, 2999, 3299, 4799, 5099, 6299, 8999, 10499, 11699, 21599, 25799, 26699, 29399, 33599, 34499, 36899, 37199, 42899, 44699, 47699, 49199, 56099, 57899, 60899, 63599, 65099, 65699, 70199, 74099, 81899, 83399, 85199, 88799, 92399, 97499, 100799, 101999, 102299

Offset

1,1

Comments

The sequence is conjecturally infinite; note that those ending in 999 straddle millenia: A158861.

Since any prime greater than 3 is congruent to 1 or 5 modulo 6, a(n)+1 is divisible by 300 (see A001359). - Hartmut F. W. Hoft, May 18 2017

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

Select[Range[100, 110000, 100], AllTrue[#+{1, -1}, PrimeQ]&]-1 (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Oct 21 2016 *)
a158277[n_] := Map[Last, Select[Map[{NextPrime[#, 1], NextPrime[#, -1]}&, Range[100, n, 100]], First[#]-Last[#]==2&]]
a158277[105000] (* data *) (* Hartmut F. W. Hoft, May 18 2017 *)

Crossrefs

Cf. A060229, A158861, A001359, A060229.

Sequence in context: A356531 A135847 A106762 * A250937 A261701 A362324

Adjacent sequences: A158274 A158275 A158276 * A158278 A158279 A158280

Keyword

nonn

Author

Ki Punches, Mar 15 2009

Extensions

Corrected by Ray Chandler and R. J. Mathar, Apr 03 2009

Status

approved