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

0,1

Comments

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

Links

Table of n, a(n) for n=0..48.

Formula

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

Example

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

Prog

(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

Crossrefs

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

Sequence in context: A259716 A033907 A033549 * A008434 A130447 A116284

Adjacent sequences: A117475 A117476 A117477 * A117479 A117480 A117481

Keyword

easy,nonn,base

Author

Enoch Haga, Mar 19 2006

Extensions

Typo in comment fixed by Franklin T. Adams-Watters, Dec 03 2009

Status

approved