A225859 Smallest k such that n numbers can be picked in {1,...,k} with no five terms in arithmetic progression.

1, 2, 3, 4, 6, 7, 8, 9, 11, 12, 13, 14, 16, 17, 18, 19, 24, 25, 27, 28, 29, 31, 33, 34, 36, 37, 38, 39, 41, 42, 43, 44, 49, 51, 52, 54, 56, 57, 58, 59, 61, 62, 63, 64, 66, 67, 68, 69, 76

Offset

1,2

References

Knuth, Donald E., Satisfiability, Fascicle 6, volume 4 of The Art of Computer Programming. Addison-Wesley, 2015, pages 135 and 190, Problem 31.

Links

Table of n, a(n) for n=1..49.

Samuel S. Wagstaff, Jr., On k-free sequences of integers, Math. Comp., 26 (1972), 767-771.

Crossrefs

This sequence is to A003004 as A065825 is to A003002.

Cf. A226066.

Sequence in context: A120518 A101888 A190241 * A020655 A188042 A236842

Adjacent sequences: A225856 A225857 A225858 * A225860 A225861 A225862

Keyword

nonn,more

Author

Don Knuth, Aug 05 2013

Status

approved