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A309974
a(1) = a(2) = a(3) = 1; a(n) = round((2*n-a(n-1)-a(n-2))/a(n-3)) for n > 3.
1
1, 1, 1, 6, 3, 3, 1, 4, 4, 12, 2, 3, 2, 12, 5, 8, 2, 5, 4, 16, 4, 6, 2, 10, 6, 18, 3, 6, 3, 17, 7, 13, 3, 7, 5, 20, 7, 10, 3, 10, 7, 22, 6, 9, 3, 13, 9, 25, 5, 8, 4, 18, 11, 20, 4, 8, 5, 26, 11, 17, 4, 9, 7, 28, 11, 13, 4, 11, 9, 30, 9, 12, 4, 15, 11, 32, 7, 11, 4, 21, 12, 33, 6, 11, 5
OFFSET
1,4
LINKS
Rémy Sigrist, Colored scatterplot of the first 30000 terms (where the color is function of n mod 6)
PROG
(PARI) q=vector(100); q[1]=q[2]=q[3]=1; for(n=4, #q, q[n]=round((2*n-q[n-1]-q[n-2])/q[n-3])); q
(Magma) I:=[1, 1, 1]; [n le 3 select I[n] else Round((2*n-Self(n-1)-Self(n-2))/Self(n-3)):n in [1..80]]; // Marius A. Burtea, Aug 25 2019
CROSSREFS
Sequence in context: A096685 A307150 A195457 * A155964 A144542 A222457
KEYWORD
nonn,easy,look
AUTHOR
Altug Alkan and Rémy Sigrist, Aug 25 2019
STATUS
approved