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A081953 Smallest Fibonacci number equal one plus the product of n (not necessarily distinct) integers > 1.

%I A081953 #21 Jun 24 2023 07:55:18
%S A081953 3,5,13,55,1597,28657,28657,121393,2971215073,2971215073,2971215073,
%T A081953 7778742049,308061521170129,308061521170129,135301852344706746049,
%U A081953 135301852344706746049,1454489111232772683678306641953
%N A081953 Smallest Fibonacci number equal one plus the product of n (not necessarily distinct) integers > 1.
%H A081953 Amiram Eldar, <a href="/A081953/b081953.txt">Table of n, a(n) for n = 1..60</a>
%F A081953 a(n) = A000045(k) for the smallest k such that A001222(A000045(k)-1) >= n.
%e A081953 a(4)= 2*3*3*3 + 1 = 55.
%e A081953 a(5) = 2*3*3*7*19 + 1 = 1597.
%p A081953 for n from 1 to 14 do for fib from 2 to 5000 do f := combinat[fibonacci](fib)-1 ; allf := op(2,ifactors(f)) ; pow := 0 : for i from 1 to nops(allf) do pow := pow + op(2,op(i,allf)) ; od : if pow >= n then printf("%d,",f+1) ; break ; fi ; od : od ; # _R. J. Mathar_, Apr 13 2006
%o A081953 (PARI) { m=3; for(n=1,30, while(bigomega(fibonacci(m)-1)<n, m++); print1(fibonacci(m),", "); ) } \\ _Max Alekseyev_, Apr 22 2010
%Y A081953 Subset of A000045.
%Y A081953 Cf. A000071, A001222, A081952.
%K A081953 nonn
%O A081953 1,1
%A A081953 _Amarnath Murthy_, Apr 02 2003
%E A081953 More terms from _R. J. Mathar_, Apr 13 2006
%E A081953 Corrected and extended by _Max Alekseyev_, Apr 22 2010