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A341267
Gaps between first elements of quadruple primes of the form {p, p+2, p+6, p+12}.
2
6, 6, 24, 60, 126, 120, 294, 450, 186, 150, 54, 6, 120, 1080, 840, 390, 84, 126, 510, 150, 144, 3300, 1230, 870, 1446, 330, 1794, 726, 1434, 3360, 1326, 264, 546, 714, 1470, 1836, 1104, 30, 1026, 204, 336, 744, 2226, 810, 240, 1050, 270, 1914, 60, 876, 1980
OFFSET
1,1
COMMENTS
Primes in the quadruple need not be sequential primes.
LINKS
James S. DeArmon, Perl program
Eric Weisstein's World of Mathematics, Prime Triplet
FORMULA
a(n) = A172454(n+1) - A172454(n).
EXAMPLE
The first 6 quadruples are (5,7,11,17), (11,13,17,23), (17,19,23,29), (41,43,47,53), (101,103,107,113), (227,229,233,239), so the first 5 terms of the sequence are 11-5=6, 17-11=6, 41-17=24, 101-41=60, 227-101=126.
MAPLE
b:= proc(n) option remember; local p; p:= `if`(n=1, 1, b(n-1));
do p:= nextprime(p);
if andmap(isprime, [p+2, p+6, p+12]) then return p fi
od
end:
a:= n-> b(n+1)-b(n):
seq(a(n), n=1..65); # Alois P. Heinz, Feb 14 2021
MATHEMATICA
Differences[Select[Prime[Range[5000]], AllTrue[#+{2, 6, 12}, PrimeQ]&]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 21 2021 *)
PROG
(Perl) See links.
CROSSREFS
Cf. A172454.
Sequence in context: A267710 A306896 A087236 * A219910 A334569 A077193
KEYWORD
nonn
AUTHOR
James S. DeArmon, Feb 07 2021
STATUS
approved