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%I #17 Mar 07 2024 15:40:40
%S 34,35,42,43,53,54,61,62,68,69,80,81,82,83,101,102,106,107,115,116,
%T 125,126,127,128,138,139,141,142,145,146,154,155,157,158,172,173,175,
%U 176,177,178,191,192,193,194,204,205,222,223,233,234,258,259,260,266,267,269,270,279,280,289,290,306,307
%N Indices of primes ending with the same decimal digit as the previous or next prime.
%H Harvey P. Dale, <a href="/A270311/b270311.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Range@ 307, Function[k, Or[k == Mod[NextPrime@ Prime@ #, 10], k == Mod[NextPrime[Prime@ #, -1], 10]]]@ Mod[Prime@ #, 10] &] (* _Michael De Vlieger_, Mar 15 2016 *)
%t PrimePi/@Select[Partition[Prime[Range[350]],3,1],Mod[#[[2]],10]==Mod[#[[1]],10]||Mod[#[[2]],10]==Mod[#[[3]],10]&][[;;,2]] (* _Harvey P. Dale_, Mar 07 2024 *)
%Y Cf. A270310.
%K nonn,base
%O 1,1
%A _Francois Alcover_, Mar 15 2016
%E More terms from _Michael De Vlieger_, Mar 15 2016
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