S000569


Number of composite numbers in the range implied by S000568(n).

0, 1, 3, 5, 7, 9, 13, 11, 11, 13, 17, 17, 21, 19, 23, 23, 25, 29, 29, 29, 33, 33, 35, 39, 41, 39, 43, 43, 47, 57, 49, 51, 51, 53, 53, 59, 57, 61, 59, 71, 63, 67, 69, 67, 69, 75, 77, 77, 81, 81, 83, 85, 83, 85, 87, 89, 95, 95, 99, 99, 97, 103, 105, 99, 105, 109

0

S000569

The graph is fairly linear, with a slope of about 1.6.

T. D. Noe, Plot of 101 terms

T. D. Noe, Table of 101 terms

Eric W. Weisstein, MathWorld: Squarefree

(Mma) nn = 50; sf = Table[0, {nn}]; found = 0; n = 1; While[found < nn, n++; c = Count[Table[SquareFreeQ[i], {i, Prime[n] + 1, Prime[n + 1] - 1}], True]; If[0 < c <= nn && sf[[c]] == 0, sf[[c]] = n; found++]]; t =Join[{2}, Prime[sf]]; Table[NextPrime[p] - p - 1, {p, t}]

Cf. S000568.

nonn,hard

T. D. Noe, Apr 10 2015

© Tony D Noe 2014-2015