A187125 Primes of the form abcdabcd..abcdabc.

1074107, 1076107, 1079107, 1093109, 1098109, 1114111, 1117111, 1131113, 1134113, 1171117, 1191119, 1193119, 1196119, 1212121, 1215121, 1218121, 1273127, 1294129, 1297129, 1311131, 1317131, 1333133, 1336133, 1371137, 1373137, 1377137, 1379137, 1398139

Offset

1,1

Comments

The sequence appears to be infinite. The number of terms below 10^1000 are 5137.

Links

Shyam Sunder Gupta, Table of n, a(n) for n = 1..2483

Example

a(2)= 1076107 is in the sequence because it is a prime of the form abcdabc.

Mathematica

s[n_]:=Select[Union@Flatten@Table[FromDigits@Flatten@Join[IntegerDigits@Table[b, {n}], {IntegerDigits@Floor[b/10]}], {b, 1000, 9999}], PrimeQ]; Array[s, 2]//Flatten

Crossrefs

Cf. A228625, A228627

Sequence in context: A342328 A070042 A258061 * A237972 A252038 A236449

Adjacent sequences: A187122 A187123 A187124 * A187126 A187127 A187128

Keyword

nonn,base

Author

Shyam Sunder Gupta, Aug 30 2013

Status

approved