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%I #11 Feb 09 2018 11:08:36
%S 1637,3109,4327,4861,6491,6803,8563,11047,11887,13441,13669,14197,
%T 17519,17827,18859,18869,20369,20431,22511,22531,22973,22993,24943,
%U 25219,26459,26479,27397,27551,28319,29453,29473,31091,32213,32401,34939,35201,35291,36353,36373
%N Primes p whose last digit is the same as that of both its predecessor prime and its successor prime.
%C 69623 is the least prime in this sequence that is equidistant from its predecessor prime (69593) and its successor prime (69653).
%e 1637 is in the sequence because it is prime with last digit 7, and both its predecessor prime (1627) and successor prime (1657) also end in 7.
%e 3109 is in the sequence because each of the three consecutive primes 3089, 3109, and 3119 ends in 9.
%e 3119 is not in the sequence: although it is prime and both it and its predecessor prime (3109) end with the digit 9, the next prime (3121) does not.
%t Select[Partition[Prime[Range[10000]], 3, 1], Mod[#[[1]], 10] == Mod[#[[2]], 10] == Mod[#[[3]], 10] &][[All, 2]]
%Y Subsequence of A290450.
%K nonn,base
%O 1,1
%A _K. D. Bajpai_, Jan 11 2018