A318873 First differences of A316156.

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, 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, 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

Offset

1,3

Links

Antti Karttunen, Table of n, a(n) for n = 1..20000

Formula

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

Prog

(PARI)
up_to = 20000;
povisin(v, n) = { forstep(j=n, 1, -1, if(v[j] == n, return(j))); (0); }; \\ Here: povisin = position_of_n_in_strictly_increasing_v
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); };
v318873 = A318873list(up_to);
A318873(n) = v318873[n];

Crossrefs

Cf. A316156.

Sequence in context: A348028 A059619 A098950 * A346403 A295924 A357669

Adjacent sequences: A318870 A318871 A318872 * A318874 A318875 A318876

Keyword

nonn

Author

Antti Karttunen, Sep 16 2018

Status

approved