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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.
1
1, 2, 1, 2, 4, 14, 74, 494, 3854, 34094, 336494, 3662894, 43579694, 562498094, 7827355694, 116800219694, 1860366043694, 31500985051694, 565032127195694, 10702123827931694, 213443957842651694, 4471022472151771694, 98137749786952411694, 2252472478027367131694
OFFSET
1,2
COMMENTS
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
LINKS
FORMULA
a(n+1) = a(n) + sum [ absolute{a(n) - a(k)}, k = 1 to n].
EXAMPLE
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)).
MAPLE
A[1]:= 1: A[2]:= 2: A[3]:= 1:
for n from 4 to 100 do
A[n]:= A[n-1] + add(abs(A[n-1]-A[k]), k=1..n-2);
od:
convert(A, list); # Robert Israel, Oct 23 2024
CROSSREFS
Sequence in context: A095067 A225564 A032259 * A371136 A245841 A011404
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Jul 06 2005
EXTENSIONS
More terms from Joshua Zucker, May 04 2006
Corrected by Charles R Greathouse IV, Jun 08 2015
STATUS
approved