A117478 Indices of associated primes in A117477.
32, 56, 175, 182, 212, 218, 227, 331, 362, 377, 386, 397, 409, 481, 508, 571, 595, 599, 728, 751, 755, 779, 821, 827, 847, 869, 878, 896, 902, 922, 940, 953, 982, 1099, 1129, 1354, 1372, 1408, 1417, 1468, 1475, 1507, 1550, 1585, 1648, 1693, 1747, 1772, 1774
Offset: 0
Examples
a(3) = 182, with SOD 11. The associated prime is 1091, also SOD 11. SODs must be prime and equal.
Programs
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UBASIC
20 'SOD prime index and SOD prime 30 Y=1 40 Y=nxtprm(Y) 50 C=C+1:print C;Y;"-"; 60 D=str(C):Z=str(Y) 70 E=len(D):F=len(Z) 80 for Q=2 to E 90 A=mid(D,Q,1):G=val(A) 100 I=I+G:print I; 110 next Q 120 for R=2 to F 130 B=mid(Z,R,1):H=val(B) 140 J=J+H:print J; 150 next R 160 if I=prmdiv(I) and J=prmdiv(J) and I=J then stop 170 I=0:J=0 180 goto 40
Formula
Find prime indices with associated primes where both SODs are the same and prime.
Extensions
Typo in comment fixed by Franklin T. Adams-Watters, Dec 03 2009
Comments