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%I #22 Jan 17 2019 13:44:07
%S 0,1,2,4,8,10,13,31,53,54,59,152,199,460,568,839,846,1295,1355,2006,
%T 2626,2846,3109,6875,9160,17764,33554,59141,65772,280709
%N Indices of primes in sequence defined by A(0) = 17, A(n) = 10*A(n-1) - 3 for n > 0.
%C Numbers n such that (150*10^n + 3)/9 is prime.
%C Numbers n such that digit 1 followed by n >= 0 occurrences of digit 6 followed by digit 7 is prime.
%C Numbers corresponding to terms <= 846 are certified primes.
%C a(31) > 3*10^5. - _Robert Price_, Nov 15 2014
%D Klaus Brockhaus and Walter Oberschelp, Zahlenfolgen mit homogenem Ziffernkern, MNU 59/8 (2006), pp. 462-467.
%H Makoto Kamada, <a href="https://stdkmd.net/nrr/1/16667.htm#prime">Prime numbers of the form 166...667</a>.
%H <a href="/index/Pri#Pri_rep">Index entries for primes involving repunits</a>
%F a(n) = A102940(n+1) - 1. - _Robert Price_, Nov 15 2014
%e 167 is prime, hence 1 is a term.
%o (PARI) a=17;for(n=0,1500,if(isprime(a),print1(n,","));a=10*a-3)
%o (PARI) for(n=0,1500,if(isprime((150*10^n+3)/9),print1(n,",")))
%Y Cf. A000533, A002275, A102940.
%K nonn,hard,more
%O 1,3
%A _Klaus Brockhaus_ and Walter Oberschelp (oberschelp(AT)informatik.rwth-aachen.de), Dec 28 2004
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
%E a(26)-a(30) derived from A102940 by _Robert Price_, Nov 15 2014
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