A328452 Primes p such that p=prime(k), prime(k+1), and prime(k+2) end in the same digit.

1627, 3089, 4297, 4831, 6481, 6793, 8543, 11027, 11867, 13421, 13649, 14177, 17509, 17807, 18839, 18859, 20359, 20411, 22501, 22511, 22963, 22973, 24923, 25189, 26449, 26459, 27367, 27541, 28309, 29443, 29453, 31081, 32203, 32381, 34919, 35171, 35281, 36343, 36353, 37087, 37223, 37243, 38923

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Example

(p,q,r) = (1627,1637,1657), are three primes which are consecutive and end in the same digit. Hence, p=1627 is a member of this sequence.

Maple

q:= 3: r:= 5: count:= 0: R:= NULL:
while count < 100 do
   p:= q; q:= r; r:= nextprime(r);
   if p-q mod 10 = 0 and q-r mod 10 = 0 then count:= count+1; R:= R, p; fi
od:
R; # Robert Israel, May 08 2020

Mathematica

First /@ Select[Partition[Prime@ Range@ 4105, 3, 1], Length@ Union@ Mod[#, 10] == 1 &] (* Giovanni Resta, Oct 16 2019 *)

Prog

(Magma) f:=func<p, m|p mod 10 eq m and NextPrime(p) mod 10 eq m and NextPrime(NextPrime(p)) mod 10 eq m>; a:=[]; for p in PrimesUpTo(40000) do if f(p, 1) or f(p, 3) or f(p, 7) or f(p, 9) then Append(~a, p); end if; end for; a; // Marius A. Burtea, Oct 16 2019
(PARI) isok(p) = {if (isprime(p), my(d = p % 10); my(q = nextprime(p+1), r = nextprime(q+1)); (d == (q % 10)) && (d == (r % 10)); ); } \\ Michel Marcus, Oct 17 2019

Crossrefs

Cf. A000040, A290450, A054681.

Sequence in context: A186846 A198510 A241493 * A202985 A063891 A254849

Adjacent sequences: A328449 A328450 A328451 * A328453 A328454 A328455

Keyword

nonn,base

Author

Philip Mizzi, Oct 15 2019

Status

approved