A071612
a(n) is the smallest prime that is the first of n consecutive primes which are all emirps.
Original entry on oeis.org
13, 13, 71, 733, 1193, 1193, 1193, 1193, 1193, 1193, 1477271183, 9387802769, 15423094826093
Offset: 1
1193,1201,1213,1217,1223,1229,1231,1237,1249,1259 are ten consecutive primes which are all emirps and 1193,1201,1213,1217,1223 is the first occurrence of five consecutive primes which are all emirps, so a(5) = a(6) = a(7) = a(8) = a(9) = a(10) = 1193.
By studying terms of the sequence
A103172 we can deduce that a(11), a(12) are 1477271183 & 9387802769. -
Farideh Firoozbakht, Jun 17 2010
A103169
Start of seven consecutive primes whose digit reversals are also prime.
Original entry on oeis.org
2, 727, 733, 1193, 1201, 1213, 1217, 11897, 18719, 79379, 125627, 334759, 334771, 743989, 910909, 920957, 928429, 941449, 1093571, 1215079, 1407181, 1466533, 1518863, 1648553, 1770829, 3170743, 3300593, 7321943, 7682687, 7755581
Offset: 1
1193, 1201, 1213, 1217, 1223, 1229 and 1231 are consecutive primes.
Their digit reversals, 3911, 1021, 3121, 7121, 3221, 9221 and 1321, are all prime.
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With[{s = Prime@ Range[10^6]}, IntegerReverse /@ Flatten@ Map[Take[#, Length@ # - 6] &, DeleteCases[SplitBy[Map[IntegerReverse, s], PrimeQ], k_ /; Or[CompositeQ@ First@ k, Length@ k < 7]]]] (* Michael De Vlieger, Jul 24 2017 *)
A103170
Start of eight consecutive primes whose digit reversals are also prime.
Original entry on oeis.org
727, 1193, 1201, 1213, 334759, 7904639, 7904651, 9094009, 9685771, 11875307, 12503017, 19776443, 32906869, 35414443, 37376201, 70252333, 71161309, 73694129, 77454067, 91528739, 91528777, 91528807, 93907523
Offset: 1
1193, 1201, 1213, 1217, 1223, 1229, 1231 and 1237 are consecutive primes.
Their digit reversals, 3911, 1021, 3121, 7121, 3221, 9221, 1321 and 7321, are all prime.
A103171
Start of nine consecutive primes whose digit reversals are also prime.
Original entry on oeis.org
1193, 1201, 7904639, 91528739, 91528777, 120890249, 154984343, 174625597, 302706311, 302706319, 312700789, 318629783, 707262887, 756791029, 777528457, 777528461, 778286917, 778286947, 923780981, 924408493, 924408497, 958610069
Offset: 1
1193, 1201, 1213, 1217, 1223, 1229, 1231, 1237 and 1249 are consecutive primes.
Their digit reversals, 3911, 1021, 3121, 7121, 3221, 9221, 1321, 7321 and 9421, are all prime.
A040104
First ten consecutive primes which are emirps.
Original entry on oeis.org
1193, 1201, 1213, 1217, 1223, 1229, 1231, 1237, 1249, 1259
Offset: 1
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Flatten[Select[Partition[Prime[Range[220]],10,1],And@@PrimeQ[ FromDigits/@ (Reverse/@(IntegerDigits/@#))]&]] (* Harvey P. Dale, May 20 2014 *)
Showing 1-5 of 5 results.
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