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a(n) = Sum_{i=0..n} T(i,n-i) where T is A049627.
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%I #15 Jun 26 2022 17:31:02

%S 1,4,8,14,22,34,48,68,92,122,156,200,248,308,374,448,530,628,732,854,

%T 984,1126,1278,1452,1634,1836,2050,2282,2526,2798,3078,3388,3714,4060,

%U 4422,4808,5206,5640,6092,6568,7060,7592,8136,8722,9328,9958,10610,11308

%N a(n) = Sum_{i=0..n} T(i,n-i) where T is A049627.

%o (PARI) T(n,k) = (n+1)*(k+1) - sum(i=0, n, sum(j=0, k, gcd(i,j)>1)); \\ A049627

%o a(n) = sum(i=0, n, T(i,n-i)); \\ _Michel Marcus_, Aug 06 2021

%Y Cf. A049627.

%Y Partial sums of A225531.

%K nonn

%O 0,2

%A _Clark Kimberling_

%E More terms from _Sean A. Irvine_, Aug 05 2021