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Row sums of A115297.
5

%I #23 Jan 05 2019 13:56:12

%S 1,3,7,13,21,31,43,55,73,91,115,139,165,193,227,263,301,339,381,423,

%T 471,517,569,625,685,745,809,871,937,1011,1089,1167,1247,1335,1425,

%U 1515,1611,1707,1809,1915,2023,2135,2249,2363,2479,2601,2735,2865,2997,3129

%N Row sums of A115297.

%H Muniru A Asiru, <a href="/A115298/b115298.txt">Table of n, a(n) for n = 1..3000</a>

%F a(n) = Sum_{k=2..n+1} (A000040(k) - A000040(ceiling(k/2))). - _Jon Maiga_, Jan 04 2019

%p a:=n->add(ithprime(k)-ithprime(ceil(k/2)),k=2..n+1): seq(a(n),n=1..60); # _Muniru A Asiru_, Jan 04 2019

%t Accumulate[Table[Prime[n] - Prime[Ceiling[n/2]], {n, 2, 51}]] (* _Jon Maiga_, Jan 04 2019 *)

%Y Cf. A115297, A000040, A000166, A008276.

%K easy,nonn

%O 1,2

%A _André F. Labossière_, Jan 19 2006

%E More terms from _André F. Labossière_, Mar 27 2006