%I A130836
%S A130836 0,1,1,1,0,1,2,2,2,2,1,1,0,1,1,2,2,3,3,2,2,1,1,2,0,2,1,1,3,2,1,3,3,1,2,
%T A130836 3,2,2,2,2,0,2,2,2,2,2,3,4,3,3,3,3,4,3,2,1,1,1,1,2,0,2,1,1,1,1,3,2,3,4,
%U A130836 4,3,3,4,4,3,2,3,1,2,2,2,3,3,0,3,3,2,2,2,1,2,2,2,3,1,2,4,4,2,1,3,2,2,2
%N A130836 Array read by antidiagonals: d(m,n) (m>=1, n>=1) = multiplicative distance
between m and n.
%C A130836 If m = p_1^e_1 * p_2^e_2 * ... * p_k^e^k, n = p_1^f_1 * p_2^f_2 * ...
* p_k^f^k we define d(m, n) = Sum[ Abs[e_i - f_i], {i, 1, k}] to
be the multiplicative distance between m and n (see A130849).
%F A130836 a(n,m) = A127185(n,m). - R. J. Mathar (mathar(AT)strw.leidenuniv.nl),
Oct 17 2007
%e A130836 Array begins:
%e A130836 0 1 1 2 1 2 1 3 ...
%e A130836 1 0 2 1 2 1 2 2 ...
%e A130836 1 2 0 3 2 1 2 4 ...
%e A130836 2 1 3 0 3 2 3 1 ...
%e A130836 ...
%p A130836 A001222 := proc(n) numtheory[bigomega](n) ; end: A127185 := proc(n,m)
local g ; g := gcd(n,m) ; RETURN(A001222(n/g)+A001222(m/g)) ; end:
A130836 := proc(n,m) A127185(n,m) ; end: for d from 1 to 17 do for
n from 1 to d do printf("%d, ",A130836(n,d-n+1)) ; od: od: - R. J.
Mathar (mathar(AT)strw.leidenuniv.nl), Oct 17 2007
%Y A130836 Half of antidiagonal sums gives A130849. First row is A001222.
%Y A130836 Sequence in context: A124752 A049241 A101080 this_sequence A152907 A078786
A102677
%Y A130836 Adjacent sequences: A130833 A130834 A130835 this_sequence A130837 A130838
A130839
%K A130836 nonn,tabl,easy
%O A130836 1,7
%A A130836 N. J. A. Sloane (njas(AT)research.att.com), Sep 28 2007
%E A130836 More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 17 2007
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