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A288022 Prime p1 of consecutive primes p1, p2, where p2 - p1 = 6, and p1, p2 are in different decades.

%I A288022 #28 Jan 19 2018 07:34:24
%S A288022 47,157,167,257,367,557,587,607,647,677,727,947,977,1097,1117,1187,
%T A288022 1217,1367,1657,1747,1777,1907,1987,2207,2287,2417,2467,2677,2837,
%U A288022 2897,2957,3307,3407,3607,3617,3637,3727,3797,4007,4357,4457,4507,4597,4657,4937,4987
%N A288022 Prime p1 of consecutive primes p1, p2, where p2 - p1 = 6, and p1, p2 are in different decades.
%C A288022 The unit digits of the numbers in the sequence are 7's.
%C A288022 Number of terms < 10^k: 0, 0, 1, 13, 81, 565, 4027, 30422, 237715, ... - _Muniru A Asiru_, Jan 09 2018
%H A288022 Muniru A Asiru, <a href="/A288022/b288022.txt">Table of n, a(n) for n = 1..10000</a>
%e A288022 47 is in the sequence since pair (47,53) is the first with difference 6 spanning a multiple of 10.
%p A288022 for n from 1 to 2000 do if [ithprime(n+1)-ithprime(n), ithprime(n) mod 5] = [6,2] then print(ithprime(n)); fi; od; # _Muniru A Asiru_, Jan 19 2018
%t A288022 a288022[n_] := Map[Last, Select[Map[{NextPrime[#, 1], NextPrime[#, -1]}&, Range[10, n, 10]], First[#]-Last[#]==6&]]
%t A288022 a288022[3000] (* data *)
%o A288022 (GAP)
%o A288022 P:=Filtered([1..20000], IsPrime);
%o A288022 P1:=List(Filtered(Filtered(List([1..Length(P)-1],n->[P[n],P[n+1]]),i->i[2]-i[1]=6),j->j[1] mod 5=2),k->k[1]); # _Muniru A Asiru_, Jul 08 2017
%Y A288022 Cf. A001359, A023201, A023203, A031924, A031925, A031928, A046117, A046132, A158277, A158861, A160370, A160440, A160500, A287049, A287050, A060229, A288021, A288024.
%K A288022 nonn
%O A288022 1,1
%A A288022 _Hartmut F. W. Hoft_, Jun 04 2017