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The sum of the next n terms of A114103.
3

%I #12 May 23 2024 05:58:45

%S 1,8,33,92,265,384,1057,1384,2475,3160,6721,5556,13273,12656,16545,

%T 21904,39457,29664,61921,46220,66381,80608,134113,86712,162825,159224,

%U 199395,185444,341881,198480,447361,349728,423093,473416,553105,434844

%N The sum of the next n terms of A114103.

%p A000217 := proc(n) n*(n+1)/2 ; end: A114103 := proc(n,k) lcm(n,A000217(n-1)+k) ; end: A114105 := proc(n) add( A114103(n,k),k=1..n) ; end: for n from 1 to 80 do printf("%d, ",A114105(n)) ; od ; # _R. J. Mathar_, May 10 2007

%t rows = 8;

%t nmax = rows (rows + 1)/2;

%t a[n_] := Sum[LCM[n, n (n - 1)/2 + k], {k, 1, n}];

%t Table[a[n], {n, 1, nmax}] (* _Jean-François Alcover_, May 23 2024, after _Ivan Neretin_ in A114103 *)

%Y Cf. A114103, A114104.

%K nonn

%O 1,2

%A _Amarnath Murthy_, Nov 21 2005

%E Corrected and extended by Matthew Ohlsen (mjo178(AT)psu.edu), Feb 26 2006

%E More terms from _R. J. Mathar_, May 10 2007