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A062894 The prime indices of sequence A067836 (that sequence is conjectured to contain only primes).

%I A062894 #12 Sep 09 2023 16:02:26
%S A062894 1,2,3,4,6,5,7,8,9,12,21,10,11,14,22,16,23,19,13,15,41,35,42,27,20,17,
%T A062894 45,39,29,33,28,54,26,37,46,61,47,59,40,31,57,18,24,58,36,43,49,64,80,
%U A062894 106,67,60,65,63,48,94,85,51,73,122,105,100,113,138,104,115,75,32,82
%N A062894 The prime indices of sequence A067836 (that sequence is conjectured to contain only primes).
%H A062894 Robert Price, <a href="/A062894/b062894.txt">Table of n, a(n) for n = 1..1000</a>
%e A062894 a(12)=10 because a(12) in sequence A067836 is 29, which is the 10th prime number.
%t A062894 Join[{1}, a = 2; f = 1; Table[f = f*a; a = NextPrime[f + 1] - f; k = 1; While[Prime[k] != a, k++]; k, {n, 2, 69}]] (* _Jayanta Basu_, Aug 10 2013 *)
%o A062894 (Python)
%o A062894 from sympy import primepi, nextprime
%o A062894 def A062894_gen(): # generator of terms
%o A062894     a, f = 2, 1
%o A062894     yield 1
%o A062894     while True:
%o A062894         yield primepi(a:=nextprime((f:=f*a)+1)-f)
%o A062894 A062894_list = list(islice(A062894_gen(),30)) # _Chai Wah Wu_, Sep 09 2023
%Y A062894 Cf. A067836.
%K A062894 nonn
%O A062894 1,2
%A A062894 Frank Buss (fb(AT)frank-buss.de), Feb 13 2002
%E A062894 Edited by _Dean Hickerson_, Jun 10 2002