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A117478 Indices of associated primes in A117477.

%I A117478 #8 Apr 21 2024 11:38:44
%S A117478 32,56,175,182,212,218,227,331,362,377,386,397,409,481,508,571,595,
%T A117478 599,728,751,755,779,821,827,847,869,878,896,902,922,940,953,982,1099,
%U A117478 1129,1354,1372,1408,1417,1468,1475,1507,1550,1585,1648,1693,1747,1772,1774
%N A117478 Indices of associated primes in A117477.
%C A117478 A subset of A033548-A033549 but here the SODs must be prime and equal
%F A117478 Find prime indices with associated primes where both SODs are the same and prime.
%e A117478 a(3) = 182, with SOD 11. The associated prime is 1091, also SOD 11. SODs must be prime and equal.
%o A117478 (UBASIC)
%o A117478 20 'SOD prime index and SOD prime
%o A117478 30 Y=1
%o A117478 40 Y=nxtprm(Y)
%o A117478 50 C=C+1:print C;Y;"-";
%o A117478 60 D=str(C):Z=str(Y)
%o A117478 70 E=len(D):F=len(Z)
%o A117478 80 for Q=2 to E
%o A117478 90 A=mid(D,Q,1):G=val(A)
%o A117478 100 I=I+G:print I;
%o A117478 110 next Q
%o A117478 120 for R=2 to F
%o A117478 130 B=mid(Z,R,1):H=val(B)
%o A117478 140 J=J+H:print J;
%o A117478 150 next R
%o A117478 160 if I=prmdiv(I) and J=prmdiv(J) and I=J then stop
%o A117478 170 I=0:J=0
%o A117478 180 goto 40
%Y A117478 Cf. A117477, A033548-A033549, A117458-A117463.
%K A117478 easy,nonn,base
%O A117478 0,1
%A A117478 _Enoch Haga_, Mar 19 2006
%E A117478 Typo in comment fixed by _Franklin T. Adams-Watters_, Dec 03 2009