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A052168
Primes at which difference pattern X4242Y (X and Y >= 6) occurs in A001223.
16
1867, 3457, 5647, 15727, 79687, 88807, 101107, 257857, 266677, 276037, 284737, 340927, 354247, 375247, 402757, 419047, 427237, 463447, 470077, 626617, 666427, 736357, 823717, 855727, 959467, 978067, 1022377, 1043587, 1068247, 1118857
OFFSET
1,1
COMMENTS
All terms are == 7 (mod 30). - Zak Seidov, May 07 2017
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..10000 (First 528 terms from Zak Seidov.)
EXAMPLE
1867 is here because the successor primes (1867),1871,1873,1877,1879 give 4242 difference pattern. The primes around this island are 1861 and 1889 in distance 6 and 10 resp. Thus the d-pattern "around 1867" is {6,4,2,4,2,10}. [corrected by Zak Seidov, May 07 2017]
MATHEMATICA
m=1867; Reap[Do[While[ PrimeQ[m] m = m + 30]; If[
m > NextPrime[m, -1] + 5 && AllTrue[m + {4, 6, 10, 12}, PrimeQ] && NextPrime[m + 12] > m + 17, Sow[m]]; m = m + 30, {10^5}]][[2, 1]] (* Zak Seidov, May 07 2017 *)
KEYWORD
nonn
AUTHOR
Labos Elemer, Jan 26 2000
STATUS
approved