cp's OEIS Frontend

A068595 Number of functions from {1,2,...,n} to {1,2,...,n} such that the sum of the function values is 0 mod 3.

%I A068595 #9 Feb 26 2024 14:16:37
%S A068595 0,2,9,85,1041,15552,274514,5592406,129140163,3333333333,95103890203,
%T A068595 2972033482752,100958368864084,3704002275186006,145964630126953125,
%U A068595 6148914691236517205,275746753962112254725,13115469358432179191808,659473218553437863041326,34952533333333333333333334
%N A068595 Number of functions from {1,2,...,n} to {1,2,...,n} such that the sum of the function values is 0 mod 3.
%C A068595 If the functions counted are those whose sum of values is 0 mod 2 (instead of 0 mod 3) it appears that we get A057065.
%C A068595 It appears that a(n) = floor((n^n)/3) for n>2.
%C A068595 This conjecture is false for n=8, n=14, and n=20. - _Sean A. Irvine_, Feb 26 2024
%H A068595 Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a068/A068595.java">Java program</a> (github)
%H A068595 <a href="http://groups.google.com/groups?hl=en&amp;th=ce34860d0a61eb2b&amp;rnum=2">sci.math thread</a> [Broken link?]
%Y A068595 Cf. A057065.
%K A068595 nonn
%O A068595 1,2
%A A068595 _John W. Layman_, Mar 13 2002
%E A068595 a(9)-a(20) from _Sean A. Irvine_, Feb 26 2024