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Balanced primes of order one ending in 1.
3

%I #12 May 26 2018 22:21:54

%S 211,1511,4691,7841,9871,11411,11731,12841,15161,17431,17851,18341,

%T 18731,20161,20201,20521,20731,21661,21911,22051,23801,25391,25621,

%U 26041,31051,34171,34631,35851,35911,36821,40111,40471,40961,44041,44741,48661,50441,51461

%N Balanced primes of order one ending in 1.

%e 211 = (188 + 211 + 213)/3 = 633/3 and 211 = 21*10 + 1.

%p p:=ithprime: a:=n->`if`(add(p(n-k),k=-1..1)=3*p(n) and modp(p(n), 10) = 1,p(n),NULL): seq(a(n),n=3..6000);

%o (GAP) P:=Filtered([1..52000],IsPrime);;

%o a:=Filtered(List(Filtered(List([0..Length(P)-3],k->List([1..3],j->P[j+k])),i->Sum(i)/3=i[2]),m->m[2]),l-> l mod 10=1);

%Y Intersection of A006562 and A030430.

%Y Cf. A303093, A303094, A303095.

%K nonn,base

%O 1,1

%A _Muniru A Asiru_, Apr 18 2018