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A125605 Triangle read by rows: T(n,k) = (T(n-1,k-1) + T(n-1,k)) / gcd(T(n-1,k-1), T(n-1,k)).

%I A125605 #6 Nov 26 2015 17:09:11
%S A125605 1,1,1,1,2,1,1,3,3,1,1,4,2,4,1,1,5,3,3,5,1,1,6,8,2,8,6,1,1,7,7,5,5,7,
%T A125605 7,1,1,8,2,12,2,12,2,8,1,1,9,5,7,7,7,7,5,9,1,1,10,14,12,2,2,2,12,14,
%U A125605 10,1,1,11,12,13,7,2,2,7,13,12,11,1,1,12,23,25,20,9,2,9,20,25,23,12,1,1,13
%N A125605 Triangle read by rows: T(n,k) = (T(n-1,k-1) + T(n-1,k)) / gcd(T(n-1,k-1), T(n-1,k)).
%C A125605 Row A264856(n) contains the first occurrence of n, n > 0. - _Reinhard Zumkeller_, Nov 26 2015
%H A125605 T. D. Noe, <a href="/A125605/b125605.txt">Rows n=0..100, flattened</a>
%o A125605 (Haskell)
%o A125605 a125605 n k = a125605_tabl !! n !! k
%o A125605 a125605_row n = a125605_tabl !! n
%o A125605 a125605_tabl = iterate f [1] where
%o A125605    f xs = zipWith (\v w -> (v + w) `div` gcd v w) ([0] ++ xs) (xs ++ [0])
%o A125605 -- _Reinhard Zumkeller_, Nov 26 2015
%Y A125605 Cf. A007318, A125606.
%Y A125605 Cf. A040000 (central terms), A131134, A264856.
%K A125605 nonn,tabl
%O A125605 0,5
%A A125605 _Franklin T. Adams-Watters_, Nov 27 2006