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%I #23 Nov 21 2020 05:09:08
%S 2,3,11,43,251,1931,19237,239347,3627181,65467067,1381237531,
%T 33547347529,926069157329,28743895441379,993969849468227,
%U 37991369810680411,1593993722216820553
%N Prime Fibonacci sequence: each term is the prime with index equal to the sum of the previous two terms.
%F a(n) = prime(a(n-1) + a(n-2)); a(1) = 2; a(2) = 3.
%e a(5) = prime(11 + 43) = prime(54) = 251.
%t t = {2, 3}; Do[AppendTo[t, Prime[t[[-1]] + t[[-2]]]], {9}]; t (* _T. D. Noe_, May 09 2013 *)
%t nxt[{a_,b_}]:={b,Prime[a+b]}; NestList[nxt,{2,3},13][[All,1]] (* _Harvey P. Dale_, Jul 18 2020 *)
%o (PARI) a(n) = if(n<3, prime(n), prime(a(n-1) + a(n-2)));
%o vector(10, n, a(n)) \\ _Altug Alkan_, Oct 02 2015
%Y Cf. A000040, A000045, A225504.
%K nonn,more
%O 1,1
%A Christopher M. Tomaszewski (cmt1288(AT)comcast.net), May 22 2005
%E Terms a(7)-a(11) corrected by _Alex Ratushnyak_, May 09 2013
%E a(12)-a(14) from _Amiram Eldar_, Feb 03 2019
%E a(15)-a(17) from _Jinyuan Wang_, Nov 21 2020
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