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Primes at which difference pattern X4Y (X and Y >= 6) occurs in A001223.
15

%I #12 Aug 17 2023 21:38:53

%S 79,127,163,379,397,439,487,499,673,739,757,769,907,937,967,1009,1213,

%T 1549,1567,1579,1597,2203,2293,2347,2389,2437,2473,2539,2617,2749,

%U 2833,2857,2953,3019,3037,3079,3187,3217,3319,3343,3613,3697,3793,3877,3907

%N Primes at which difference pattern X4Y (X and Y >= 6) occurs in A001223.

%H Michael De Vlieger, <a href="/A052162/b052162.txt">Table of n, a(n) for n = 1..10000</a>

%e 127 is in the sequence because 127 + 4 = 131 is prime, but the difference pattern around 127 is {[113] 14 [127] 4 [131] 6 [137]}.

%t s = Differences@ Prime@ Range[600]; Prime@ Select[Position[s, 4][[All, 1]], And[s[[# - 1]] >= 6, s[[# + 1]] >= 6] &] (* _Michael De Vlieger_, Aug 17 2023 *)

%Y Cf. A001223, A052160, A052162-A052168, A022008, A047078.

%K nonn

%O 1,1

%A _Labos Elemer_, Jan 26 2000