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Interprimes (A024675) == 2 (mod 3).
1

%I #8 Jun 04 2023 14:50:29

%S 26,50,56,86,134,170,176,236,254,260,266,356,386,446,473,506,515,560,

%T 566,590,596,650,656,680,803,944,950,974,980,1016,1100,1106,1184,1190,

%U 1220,1226,1268,1286,1313,1364,1370,1436,1496,1505,1517,1556,1604,1616

%N Interprimes (A024675) == 2 (mod 3).

%C In other words, a(n) -/+ d are consecutive primes;

%C all d's are multiples of 3 and most d's are even;

%H Harvey P. Dale, <a href="/A137263/b137263.txt">Table of n, a(n) for n = 1..1000</a>

%e Examples of pairs {a(n),d} with first occurrences of d:

%e {26,3}, {473,6}, {1268,9}, {4535,12}, {5366,15}, {9569,18}, {38522,21}, {28253,24}, {40316,27}, {43361,30}, {162176,33}, {31433,36}, {370988,39}, {461759,42}, {576836,45}, {360701,48}, {492170,57}.

%t Select[Mean/@Partition[Prime[Range[2,300]],2,1],Mod[#,3]==2&] (* _Harvey P. Dale_, Jun 04 2023 *)

%Y Cf. A024675.

%K nonn

%O 1,1

%A _Zak Seidov_, Mar 12 2008, Mar 22 2008