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A369980
Run lengths in A369001.
3
1, 7, 1, 2, 1, 2, 2, 3, 2, 3, 1, 2, 1, 4, 1, 1, 1, 3, 1, 4, 1, 4, 1, 1, 2, 2, 1, 1, 1, 7, 1, 2, 2, 6, 2, 3, 1, 3, 1, 1, 1, 3, 3, 1, 1, 12, 1, 2, 1, 3, 2, 2, 1, 1, 1, 1, 2, 4, 1, 3, 1, 1, 1, 5, 1, 1, 3, 2, 1, 6, 1, 3, 1, 1, 1, 2, 1, 4, 1, 2, 1, 4, 1, 2, 1, 2, 1, 1, 1, 1, 3, 2, 1, 8, 1, 1, 1, 1, 1, 3, 1, 2, 2, 1, 1
OFFSET
1,2
LINKS
PROG
(PARI)
up_to = 105;
A083345(n) = { my(f=factor(n)); numerator(vecsum(vector(#f~, i, f[i, 2]/f[i, 1]))); };
A369001(n) = !(A083345(n)%2);
A369980list(up_to) = { my(v=vector(up_to), oc=A369001(1), nc, n=0, on=1, k=0); while(k<up_to, n++; nc = A369001(n); if(nc!=oc, oc=nc; k++; v[k] = (n-on); on=n)); (v); }
v369980 = A369980list(up_to);
A369980(n) = v369980[n];
CROSSREFS
Sequence in context: A199001 A350048 A111037 * A090202 A030172 A040052
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 09 2024
STATUS
approved