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%I #8 Sep 16 2018 21:43:16
%S 1,3,6,12,19,27,36,49,64,81,99,118,138,169,201,240,280,323,378,437,
%T 500,564,629,695,762,830,899,969,1040,1112,1185,1271,1376,1482,1589,
%U 1697,1806,1916,2027,2145,2280,2416,2553,2709,2866,3024,3183,3343,3504,3666,3829,3993,4158,4324,4491,4675,4860,5046,5233,5428
%N Partial sums of A316156.
%H Antti Karttunen, <a href="/A318872/b318872.txt">Table of n, a(n) for n = 1..20000</a>
%F a(n) = Sum_{k=1..n} A316156(k).
%o (PARI)
%o up_to = 10000;
%o povisin(v,n) = { forstep(j=n,1,-1, if(v[j] == n, return(j))); (0); }; \\ Here: povisin = position_of_n_in_strictly_increasing_v
%o A318872list(up_to) = { my(v316156 = vector(up_to), v318872 = vector(up_to), k, s); v316156[1] = v318872[1] = 1; for(n=2, up_to, k = 1+v316156[n-1]; if(povisin(v316156, n-1), s = v318872[n-1]; while((s+k)%(n-1), k++)); v316156[n] = k; v318872[n] = v318872[n-1] + v316156[n]); (v318872); };
%o v318872 = A318872list(up_to);
%o A318872(n) = v318872[n];
%Y Cf. A316156.
%K nonn
%O 1,2
%A _Antti Karttunen_, Sep 16 2018