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 A109851 a(1) = 1, a(2) = 2; for n > 2, sum of absolute differences of all combinations of pairs of previous terms. 0

%I

%S 1,2,1,2,4,14,74,494,3854,34094,336494,3662894,43579694,562498094,

%T 7827355694,116800219694,1860366043694,31500985051694,565032127195694,

%U 10702123827931694,213443957842651694,4471022472151771694,98137749786952411694,2252472478027367131694

%N a(1) = 1, a(2) = 2; for n > 2, sum of absolute differences of all combinations of pairs of previous terms.

%C The final digits approach a limit. That is, after the first few terms, all the terms end in 70194710743368411694 and as more terms go by, even more digits remain constant. - _Joshua Zucker_, May 04 2006

%F a(n+1) = a(n) + sum [ absolute{a(n) - a(k)}, k = 1 to n].

%e 14 is the next term after 4= a(5), 14 = 4 + abs(4-a(1)) + abs(4-a(2)) + abs( 4-a(3)) + abs(4-a(4)).

%K nonn

%O 1,2

%A _Amarnath Murthy_, Jul 06 2005

%E More terms from _Joshua Zucker_, May 04 2006

%E Corrected by _Charles R Greathouse IV_, Jun 08 2015

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Last modified December 7 18:19 EST 2021. Contains 349585 sequences. (Running on oeis4.)