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 A370158 a(n) is the number of prime quadruples of the form {p, p+2, p+6, p+12} with p < 10^n. 0
 0, 1, 4, 8, 24, 76, 313, 1644, 9397, 56734, 361386, 2417777, 16785520, 120150723, 882578840 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS These quadruples are adjacent twin/cousin/sexy prime pairs, and may consist of non-consecutive primes (see A086140). LINKS Table of n, a(n) for n=0..14. EXAMPLE The third term, the count of quad primes < 10^2, is 4 and they are: (5,7,11,17), (11,13,17,23), (17,19,23,29), (41,43,47,53). The first term, the count of quad primes <10^0, is 0 since the smallest prime is 2. PROG (Perl) use ntheory ':all'; use bigint; sub a { my \$count = () = sieve_prime_cluster(1, 10**\$_[0], 2, 6, 12) }; \$| = 1; for (0..12) { print(a(\$_), ", ") } # Daniel Suteu, Feb 23 2024 CROSSREFS Cf. A007530, A086140, A341267. Sequence in context: A334324 A010366 A222356 * A214201 A265185 A240530 Adjacent sequences: A370155 A370156 A370157 * A370159 A370160 A370161 KEYWORD nonn,more AUTHOR James S. DeArmon, Feb 10 2024 EXTENSIONS a(8)-a(11) from Hugo Pfoertner, Feb 10 2024 a(12) from Daniel Suteu, Feb 23 2024 a(13)-a(14) from Martin Ehrenstein, Feb 29 2024 STATUS approved

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Last modified August 14 15:00 EDT 2024. Contains 375165 sequences. (Running on oeis4.)