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 A187125 Primes of the form abcdabcd..abcdabc. 1
 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 (list; graph; refs; listen; history; text; internal format)
 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: A160687 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

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Last modified April 6 09:00 EDT 2020. Contains 333268 sequences. (Running on oeis4.)