a(n) = smallest Fib no. >a(n-1) such that sum of first n terms is prime

Neil Fernandez primeness at borve.demon.co.uk
Sat Dec 21 20:21:20 CET 2002


Doing this the other way round gives:

2, 3, 8, 34, 144, 46368

a(n) = smallest Fib.no. > a(n-1) such that sum of first n terms is prime

a(7), if it exists, > 10^15



The sequence of Fibonacci indices of the above terms is:

3, 4, 6, 9, 12, 24

and all terms > 4 are multiples of 3 because the Fibonacci numbers added
must from then on all be even, and u(k) is even only if k is a multiple
of 3.

Neil
-- 
Neil Fernandez





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