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A110351(n)/T(n) where T(n) is the n-th triangular number.
3

%I #9 Aug 09 2015 00:48:05

%S 2,1,5,11,2,4,41,55,13,17,7,9,32,1,26,239,59,67,14,2,12,104,60,66,137,

%T 149,46,50,23,25,929,116,20,5,39,65,314,40,6,230,34,36,117,4,82,494,

%U 219,229,563,54,27,146,662,97,9,49,91,797,220,228,884,11,740,614,18,122,251

%N A110351(n)/T(n) where T(n) is the n-th triangular number.

%p A110351 := proc(n) local k ; for k from 1 to n*(n+1) do if (k*(2*n+k+1)) mod (n*(n+1)) =0 then RETURN(k*(n+(k+1)/2)) ; fi ; od ; RETURN(0) ; end: A110352 := proc(n) 2*A110351(n)/(n*(n+1)) ; end: for n from 1 to 100 do printf("%d, ",A110352(n)) ; od ; # _R. J. Mathar_, May 02 2007

%t Do[t = n*(n + 1)/2; k = 1; While[Mod[k*n + k*(k + 1)/2, t] > 0, k++ ]; Print[(k*n + k*(k + 1)/2)/((n*(n + 1))/2)], {n, 1, 60}] (* _Stefan Steinerberger_, Feb 17 2006 *)

%Y Cf. A110351, A110353.

%K nonn

%O 1,1

%A _Amarnath Murthy_, Jul 21 2005

%E More terms from _Stefan Steinerberger_, Feb 17 2006

%E More terms from _R. J. Mathar_, May 02 2007