A052356 Least prime in A031932 (lesser of 14-twins) whose distance to the next 14-twin is 6*n.

24749, 293, 3833, 21467, 23417, 14159, 3779, 18353, 773, 4817, 18959, 2939, 863, 7607, 3677, 8039, 5939, 2633, 7727, 13367, 51839, 51659, 7043, 5153, 8447, 26189, 1409, 113, 7853, 1847, 13859, 43223, 2423, 24533, 65867, 50909, 19763, 15173, 15527, 86477, 55229

Offset

3,1

Comments

The smallest distance between 14-twins [A052380(7)] is 18 and its minimal increment is 6.

a(n) = p is the first prime initiating [p, p+14, p+6n, p+6n+14] quadruple and prime difference pattern of [14, 6n-14, 14].

Links

Amiram Eldar, Table of n, a(n) for n = 3..1002

Example

n = 4 results in [293,307,317,331] primes pattern and [14,24,14] difference pattern with 2 further primes (311 and 313) in the central gap.

Mathematica

seq[m_] := Module[{p = Prime[Range[m]], d, i, pp, dd, j}, d = Differences[p]; i = Position[d, 14] // Flatten; pp = p[[i]]; dd = Differences[pp]/6 - 2; j = TakeWhile[FirstPosition[dd, #] & /@ Range[Max[dd]] // Flatten, ! MissingQ[#] &]; pp[[j]]]; seq[10000] (* Amiram Eldar, Mar 05 2025 *)

Prog

(PARI) list(len) = {my(s = vector(len), c = 0, p1 = 2, q1 = 0, q2, d); forprime(p2 = 3, , if(p2 == p1 + 14, q2 = p1; if(q1 > 0, d = (q2 - q1)/6 - 2; if(d <= len && s[d] == 0, c++; s[d] = q1; if(c == len, return(s)))); q1 = q2); p1 = p2); } \\ Amiram Eldar, Mar 05 2025

Crossrefs

Cf. A031932, A052380, A052381, A053325.

Cf. A052350, A052351, A052352, A052353, A052354, A052355, A052357, A052358, A052359.

Sequence in context: A321148 A216069 A204481 * A334024 A184093 A252639

Adjacent sequences: A052353 A052354 A052355 * A052357 A052358 A052359

Keyword

nonn

Author

Labos Elemer, Mar 07 2000

Extensions

Name and offset corrected by Amiram Eldar, Mar 05 2025

Status

approved