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First differences of A316156.
2

%I #6 Sep 16 2018 21:43:23

%S 1,1,3,1,1,1,4,2,2,1,1,1,11,1,7,1,3,12,4,4,1,1,1,1,1,1,1,1,1,1,13,19,

%T 1,1,1,1,1,1,7,17,1,1,19,1,1,1,1,1,1,1,1,1,1,1,17,1,1,1,8,1,1,1,20,9,

%U 4,4,4,4,4,4,4,4,4,1,1,1,1,1,1,1,1,1,1,1,1,16,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,25

%N First differences of A316156.

%H Antti Karttunen, <a href="/A318873/b318873.txt">Table of n, a(n) for n = 1..20000</a>

%F a(n) = A316156(n+1) - A316156(n).

%o (PARI)

%o up_to = 20000;

%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 A318873list(up_to) = { my(v316156 = vector(1+up_to), v318872 = vector(1+up_to), v318873 = vector(up_to), k, s); v316156[1] = v318872[1] = 1; for(n=2, up_to+1, 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]; v318873[n-1] = v316156[n] - v316156[n-1]); (v318873); };

%o v318873 = A318873list(up_to);

%o A318873(n) = v318873[n];

%Y Cf. A316156.

%K nonn

%O 1,3

%A _Antti Karttunen_, Sep 16 2018