login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A051010
Triangle T(m,n) giving of number of steps in the Euclidean algorithm for gcd(m,n) with 0<=m<n.
11
0, 0, 1, 0, 1, 2, 0, 1, 1, 2, 0, 1, 2, 3, 2, 0, 1, 1, 1, 2, 2, 0, 1, 2, 2, 3, 3, 2, 0, 1, 1, 3, 1, 4, 2, 2, 0, 1, 2, 1, 2, 3, 2, 3, 2, 0, 1, 1, 2, 2, 1, 3, 3, 2, 2, 0, 1, 2, 3, 3, 2, 3, 4, 4, 3, 2, 0, 1, 1, 1, 1, 3, 1, 4, 2, 2, 2, 2, 0, 1, 2, 2, 2, 4, 2, 3, 5, 3, 3, 3, 2, 0, 1, 1, 3, 2, 3, 2, 1, 3, 4, 3
OFFSET
1,6
LINKS
Eric Weisstein's World of Mathematics, Euclidean Algorithm.
MATHEMATICA
t[m_, n_] := For[r[-1]=m; r[0]=n; k=1, True, k++, r[k] = Mod[r[k-2], r[k-1]]; If[r[k] == 0, Return[k-1]]]; Table[ t[m, n] , {n, 1, 14}, {m, 0, n-1}] // Flatten (* Jean-François Alcover, Oct 25 2012 *)
PROG
(Haskell)
a051010 n k = snd $ until ((== 0) . snd . fst)
(\((x, y), i) -> ((y, mod x y), i + 1)) ((n, k), 0)
a051010_row n = map (a051010 n) [0..n-1]
a051010_tabl = map a051010_row [1..]
-- Reinhard Zumkeller, Jun 27 2013
CROSSREFS
Cf. A049826.
Cf. A130130 (central terms).
Sequence in context: A048823 A173655 A025871 * A328342 A214269 A130027
KEYWORD
nonn,nice,tabl
STATUS
approved