A336433 Number of sequences of n numbers from 1 to n that do not have a subsequence that adds up to n.

0, 0, 0, 1, 5, 68, 403, 7257, 61686, 1174434, 13810620, 335547727, 3783688286, 124486381056, 1935430229612, 55798127869680, 1058567311736669, 39819079382937334, 717447490866241055, 32064848897165970340, 666062878027691348450, 28916070816360797805534

Offset: 0

Author

Pierre Abbat, Jul 21 2020

Keywords

• nonn

Comments

The sequence is bounded above for odd n by (((n-1)/2)^n)*(2^((n-1)/2)).

Growth appears to be slightly faster than exponential, but irregular, with odd-numbered terms larger than the trend.

Examples

			For n=3, the only solution is 2,2,2.
For n=4, the 5 solutions are 3,3,3,3 and the four permutations of 3,3,3,2.
		

Links

• Christopher L. Reedy, Table of n, a(n) for n = 1..30
• Pierre Abbat, Fullproc
• Christopher L. Reedy, sequence.py

Crossrefs

Cf. A000312.

Programs

Python

# See sequence.py link.

Extensions

a(19)-a(21) from Christopher L. Reedy, Aug 06 2020