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A238098 Number of cubic polynomials with coefficients from {1..n} for which all three roots are integers. 2
0, 0, 1, 1, 2, 3, 4, 5, 7, 8, 10, 12, 13, 15, 19, 21, 23, 25, 27, 30, 34, 36, 39, 44, 46, 49, 54, 57, 60, 64, 67, 72, 76, 79, 85, 91, 92, 95, 100, 106, 109, 115, 117, 122, 129, 132, 136, 147, 150, 154 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

A generalization of A006218 and A238096.

REFERENCES

D. Andrica and E. J. Ionascu, On the number of polynomials with coefficients in [n], An. St. Univ. Ovidius Constanta, 2013, to appear.

LINKS

Table of n, a(n) for n=1..50.

FORMULA

a(n) = Sum_{k=1..n} floor(n/k)*A238097(k).

CROSSREFS

Sequence in context: A184105 A062469 A340758 * A328283 A034156 A034157

Adjacent sequences:  A238095 A238096 A238097 * A238099 A238100 A238101

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Feb 22 2014

STATUS

approved

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Last modified September 23 20:42 EDT 2021. Contains 347617 sequences. (Running on oeis4.)