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A067120 a(n) = floor(X/Y) where X = concatenation of first n odd numbers in increasing order and Y = n-th triangular number.

%I A067120 #18 Dec 03 2023 17:00:51
%S A067120 1,4,22,135,905,64662,4849682,377197536,30175802922,2468929330031,
%T A067120 205744110835938,17409117070733232,1492210034634277058,
%U A067120 129324869668304011738,11315926095976601027106,998464067292053031803477,88752361537071380604753549,7941000769106386685688475516
%N A067120 a(n) = floor(X/Y) where X = concatenation of first n odd numbers in increasing order and Y = n-th triangular number.
%H A067120 Harvey P. Dale, <a href="/A067120/b067120.txt">Table of n, a(n) for n = 1..353</a>
%e A067120 a(4) floor[1357/(1+2+3+4)] = floor[135.7] = 135.
%p A067120 for i from 1 to 33 do n := 2*i-1:c := n:n := n-2:while(n>0) do g := floor(log(c)/log(10)):c := c+10^(g+1)*n:n := n-2:end do:a[i] := floor(2*c/i/(i+1)):end do:q2 := seq(a[j],j=1..33);
%t A067120 With[{nn=20},Table[Floor[FromDigits[Flatten[IntegerDigits/@Range[1,2n-1,2]]]/((n(n+1))/2)],{n,nn}]] (* _Harvey P. Dale_, Feb 22 2020 *)
%Y A067120 Cf. A067112-A067119.
%K A067120 easy,nonn,base,less
%O A067120 1,2
%A A067120 _Amarnath Murthy_, Jan 08 2002
%E A067120 More terms from _Sascha Kurz_, Mar 23 2002
%E A067120 Edited by _Charles R Greathouse IV_, Apr 27 2010