A117478 - OEIS

%I #8 Apr 21 2024 11:38:44

%S 32,56,175,182,212,218,227,331,362,377,386,397,409,481,508,571,595,

%T 599,728,751,755,779,821,827,847,869,878,896,902,922,940,953,982,1099,

%U 1129,1354,1372,1408,1417,1468,1475,1507,1550,1585,1648,1693,1747,1772,1774

%N Indices of associated primes in A117477.

%C A subset of A033548-A033549 but here the SODs must be prime and equal

%F Find prime indices with associated primes where both SODs are the same and prime.

%e a(3) = 182, with SOD 11. The associated prime is 1091, also SOD 11. SODs must be prime and equal.

%o (UBASIC)

%o 20 'SOD prime index and SOD prime

%o 30 Y=1

%o 40 Y=nxtprm(Y)

%o 50 C=C+1:print C;Y;"-";

%o 60 D=str(C):Z=str(Y)

%o 70 E=len(D):F=len(Z)

%o 80 for Q=2 to E

%o 90 A=mid(D,Q,1):G=val(A)

%o 100 I=I+G:print I;

%o 110 next Q

%o 120 for R=2 to F

%o 130 B=mid(Z,R,1):H=val(B)

%o 140 J=J+H:print J;

%o 150 next R

%o 160 if I=prmdiv(I) and J=prmdiv(J) and I=J then stop

%o 170 I=0:J=0

%o 180 goto 40

%Y Cf. A117477, A033548-A033549, A117458-A117463.

%K easy,nonn,base

%O 0,1

%A _Enoch Haga_, Mar 19 2006

%E Typo in comment fixed by _Franklin T. Adams-Watters_, Dec 03 2009