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A178767
Values of gcd(Fibonacci(n), Fibonacci(n+3)+2) sorted with no repeats.
1
1, 2, 3, 4, 5, 7, 13, 36, 47, 68, 89, 123, 233, 644, 843, 1220, 1597, 2207, 4181, 11556, 15127, 21892, 28657, 39603, 75025, 207364, 271443, 392836, 514229, 710647, 1346269, 3720996, 4870847, 7049156, 9227465, 12752043, 24157817, 66770564, 87403803, 126491972
OFFSET
1,2
LINKS
FORMULA
G.f.: (2*x^14 + 3*x^12 + x^11 + 4*x^10 + 7*x^9 + 5*x^7 - 7*x^6 - 5*x^5 - 4*x^4 - 3*x^3 - 2*x^2 - x) / (-x^12 + 18*x^6 - 1). - Alois P. Heinz, Dec 29 2010
MAPLE
a:= proc(n) local l, r;
l:= [1, 2, 3, 4, 5, 7, 13, 36, 47, 68, 89, 123, 233, 644];
`if`(n<15, l[n], (<<0|1>, <-1|18>> ^iquo(n-3, 6, 'r').
<<l[3+r], l[9+r]>>) [1, 1])
end:
seq(a(n), n=1..40); # Alois P. Heinz, Dec 29 2010
MATHEMATICA
Take[Union@Table[GCD[Fibonacci[n], Fibonacci[n+3]+2], {n, 1000}], 60]
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved