%N Array T(n,k) read by antidiagonals: T(n,2k+1) = 2k+1. T(n,2k) = 2^n*k.
%C The array is constructed multiplying the even-indexed A026741(k) by 2^n, and keeping the odd-indexed A026471(k) as they are.
%C Connections to the hydrogen spectrum: The squares of the second row are T(1,k)^2 = A001477(k)^2 = A000290(k) which are the denominators of the Lyman lines (see A171522). The squares of the row T(2,k) are in A154615, denominators of the Balmer series. Row T(3,k) is related to A106833 and A061038.
%e The array starts in row n=0 with columns k>=0 as:
%e 0,1,1,3,2,5,3,7,4, A026741
%e 0,1,2,3,4,5,6,7,8, A001477
%e 0,1,4,3,8,5,12,7,16, A022998
%e 0,1,8,3,16,5,24,7,32, A144433
%p A168068 := proc(n,k) if type(k,'odd') then k; else 2^(n-1)*k ; end if; end proc: # R. J. Mathar, Jan 22 2011
%A _Paul Curtz_, Nov 18 2009