OFFSET
1,1
COMMENTS
See also the less restrictive A054701 where the gaps are multiples 6n. - M. F. Hasler, Nov 06 2018
LINKS
EXAMPLE
a(5) = 642427, 642457, 642487, 642517 are the smallest consecutive primes with 3 consecutive gaps of 30, cf. A052243.
From M. F. Hasler, Nov 06 2018: (Start)
Other terms are also initial terms of corresponding sequences:
a(2) = 111497 = A033447(1), start of first CPAP-4 with common gap of 12,
a(4) = 1397609 = A052242(1), start of first CPAP-4 with common gap of 24,
a(7) = 23921257 = A058323(1), start of first CPAP-4 with common gap of 42,
a(8) = 55410683 = A067388(1), start of first CPAP-4 with common gap of 48,
a(9) = 400948369 = A259224(1), start of first CPAP-4 with common gap of 54,
a(11) = 1140813701 = A287547(1), start of first CPAP-4 with common gap of 66,
a(12) = 491525857 = A287550(1), start of first CPAP-4 with common gap of 72,
a(13) = 998051413 = A287171(1), start of first CPAP-4 with common gap of 78,
a(14) = 2060959049 = A287593(1), start of first CPAP-4 with common gap of 84,
MATHEMATICA
Transpose[Flatten[Table[Select[Partition[Prime[Range[2000000]], 4, 1], Union[ Differences[ #]] =={6n}&, 1], {n, 7}], 1]][[1]] (* Harvey P. Dale, Aug 12 2012 *)
PROG
(PARI) a(n, p=[2, 0, 0], d=6*[n, n, n])={while(p+d!=p=[nextprime(p[1]+1), p[1], p[2]], ); p[3]-d[3]} \\ after M. F. Hasler in A052243; Graziano Aglietti (mg5055(AT)mclink.it), Aug 22 2010, Corrected by M. F. Hasler, Nov 06 2018
(PARI) A052239(n, p=2, c, o)={n*=6; forprime(q=p+1, , if(p+n!=p=q, next, q!=o+2*n, c=2, c++>3, break); o=q-n); o-n} \\ M. F. Hasler, Nov 06 2018
CROSSREFS
KEYWORD
nice,nonn
AUTHOR
Labos Elemer, Jan 31 2000
EXTENSIONS
More terms from Labos Elemer, Jan 04 2002
a(7) corrected and more terms added by Graziano Aglietti (mg5055(AT)mclink.it), Aug 22 2010
a(15)-a(20) from Donovan Johnson, Oct 05 2010
a(21)-a(23) from Donovan Johnson, May 23 2011
STATUS
approved