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A307890 Prime centuries with at least one prime year in each decade and exactly one prime year in decades 1 to 8.

%I A307890 #11 May 17 2024 00:32:54
%S A307890 3677,4073,16447,118463,211217,357131,368153,582017,932413,1172777,
%T A307890 1239443,2284027,2421473,3900931,4943777,5046053,6850463,6966059,
%U A307890 8046347,10448783,11548777,12849937,15198811,16031237,17315087,19443679,20075687,20434811,20462861,20614667
%N A307890 Prime centuries with at least one prime year in each decade and exactly one prime year in decades 1 to 8.
%C A307890 In other words, prime numbers p such that there are ten consecutive primes between p*100-100 and p*100, each of them in a different decade. (The P-div-10s are all different.) - _Don Reble_, May 02 2019
%e A307890 4073 is in the sequence, representing the prime sequence 407203, 407207, 407219, 407221, 407233, 407249, 407257, 407263, 407273, 407287, 407291, 407299, with 2 primes in decades 0 and 9, and 1 prime in decades 1 to 8. - _R. J. Mathar_, May 03 2019
%p A307890 isA307890 := proc(n)
%p A307890     local p, dec ;
%p A307890     if not isprime(n) then
%p A307890         false;
%p A307890     else
%p A307890         p := 100*(n-1) ;
%p A307890         p := prevprime(p+10) ;
%p A307890         for dec from 0 to 9 do
%p A307890             if modp(floor(p/10), 10) <> dec then
%p A307890                 return false;
%p A307890             end if;
%p A307890             p := nextprime(p) ;
%p A307890         end do:
%p A307890         true ;
%p A307890     end if;
%p A307890 end proc:
%p A307890 for i from 1 do
%p A307890     p := ithprime(i) ;
%p A307890     if isA307890(p) then
%p A307890         printf("%d, \n", p) ;
%p A307890     end if;
%p A307890 end do: # _R. J. Mathar_, May 03 2019
%Y A307890 Cf. A156115, super set of the primes in A103608.
%K A307890 nonn,less
%O A307890 1,1
%A A307890 _Zak Seidov_, Feb 27 2009