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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A379750 First prime of cousin prime pairs which differ, in their binary representation, by a single bit.

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%I A379750 #48 Mar 02 2025 08:00:29
%S A379750 3,19,43,67,97,163,193,307,313,379,457,499,643,673,739,769,859,883,
%T A379750 907,937,1009,1297,1483,1489,1579,1609,1867,1873,1993,2083,2137,2203,
%U A379750 2347,2377,2473,2539,2617,2659,2683,2689,2707,2833,2857,2953,3019,3163,3187,3217
%N A379750 First prime of cousin prime pairs which differ, in their binary representation, by a single bit.
%C A379750 The first prime of a cousin prime pair is a prime p for which p+4 is also prime.
%C A379750 The only way for p and p+4 to differ at a single bit position is when p has a 0 bit at its "4" position, so p == {0,1,2,3} (mod 8), and so this sequence is the intersection of A023200 and A047471.
%e A379750 3 is a term since it's a cousin prime with 7 and their respective binary representations 011 and 111 differ at a single bit position.
%e A379750 13 is not a term since, although it's a cousin prime with 17, their respective binary representations 1101 and 10001 differ at more than a single bit position.
%t A379750 Select[Prime[Range[480]], PrimeQ[#+4]&&Mod[#,8]<4&] (* _James C. McMahon_, Mar 01 2025 *)
%o A379750 (Python)
%o A379750 import sympy
%o A379750 def ok(n): return (n&5)==1 and sympy.isprime(n) and sympy.isprime(n+4)
%Y A379750 Cf. A023200 (cousin primes), A047471, A071695.
%K A379750 nonn,base
%O A379750 1,1
%A A379750 _James S. DeArmon_, Jan 01 2025
%E A379750 a(45)-a(48) from _James C. McMahon_, Mar 01 2025