A270310 Primes ending with the same decimal digit as the previous or next prime.

139, 149, 181, 191, 241, 251, 283, 293, 337, 347, 409, 419, 421, 431, 547, 557, 577, 587, 631, 641, 691, 701, 709, 719, 787, 797, 811, 821, 829, 839, 887, 907, 919, 929, 1021, 1031, 1039, 1049, 1051, 1061, 1153, 1163, 1171, 1181, 1249, 1259, 1399, 1409, 1471, 1481, 1627, 1637, 1657, 1699, 1709

Offset

1,1

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Robert J. Lemke Oliver and Kannan Soundararajan, Unexpected biases in the distribution of consecutive primes, arXiv:1603.03720 [math.NT], 2016.

Formula

a(n) = prime(A270311(n)).

Mathematica

Select[Prime@ Range@ 300, Function[k, Or[k == Mod[NextPrime@ #, 10], k == Mod[NextPrime[#, -1], 10]]]@ Mod[#, 10] &] (* Michael De Vlieger, Mar 15 2016 *)
Select[Partition[Prime[Range[300]], 3, 1], Mod[#[[2]], 10]==Mod[#[[1]], 10]||Mod[#[[2]], 10]== Mod[#[[3]], 10]&][[;; , 2]] (* Harvey P. Dale, Jul 21 2023 *)

Prog

(PARI) is(n)=isprime(n) && ((nextprime(n+1)-n)%10==0 || (n-precprime(n-1))%10==0) \\ Charles R Greathouse IV, Mar 15 2016

Crossrefs

Cf. A270311.

Sequence in context: A340800 A333135 A361342 * A047652 A308788 A308796

Adjacent sequences: A270307 A270308 A270309 * A270311 A270312 A270313

Keyword

base,easy,nonn

Author

Francois Alcover, Mar 15 2016

Extensions

a(15)-a(55) from Charles R Greathouse IV, Mar 15 2016

Status

approved