Add per-file copyright notices & contact info

This is the safest thing to do to ensure my software is free while
avoiding legal trouble ... hopefully, I'm not a lawyer!

1 files changed, 18 insertions, 0 deletions

diff --git a/README.org b/README.org
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+++ b/README.org
@@ -86,3 +86,21 @@ The MTC is an estimate of how difficult it is to learn a radix's multiplication
 The radix's natural logarithm indicates its information density - how much information it can fit into a digit.  Radices with higher logarithms will be able to count higher with fewer digits, and approximations will be more accurate for the same number of decimal places.
 
 Specifically, numbers in radix a will have ln(b)/ln(a) times as many digits as numbers in radix b.  For example, ln(20)/ln(10)≈1.30, so decimal numbers will have around 30% more digits than vigesimal numbers.
+** Copyright & Contact Info
+radix_info: gives some information about number radices
+Copyright (C) 2023  Adrien Hopkins
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of version 3 of the GNU General Public License
+as published by the Free Software Foundation.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+I can be found at <adrien.p.hopkins@gmail.com>.
+I accept emailed patches there (more info at https://git-send-email.io/)!