OFFSET
1,4
COMMENTS
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..1275 (first 50 antidiagonals)
Eric Weisstein's World of Mathematics, Totient Function.
Wikipedia, Euler's totient function.
EXAMPLE
Array begins:
n\k| 2 3 4 5 6 7 8 9 ...
---+---------------------------------------------------
1 | 1 1 2 2 4 2 6 4 ...
2 | 1 2 4 4 12 8 18 16 ...
3 | 2 4 12 20 56 36 144 96 ...
4 | 2 8 32 48 216 160 432 640 ...
5 | 6 22 120 280 1240 1120 5400 5280 ...
6 | 6 48 288 720 5040 6048 23328 27648 ...
7 | 18 156 1512 5580 31992 37856 254016 340704 ...
8 | 16 320 4096 14976 139968 192000 829440 1966080 ...
...
MATHEMATICA
A369291[n_, k_] := EulerPhi[k^n - 1]/n;
Table[A369291[k, n-k+2], {n, 15}, {k, n}] (* Paolo Xausa, Jun 17 2024 *)
PROG
(PARI) T(n, k) = eulerphi(k^n-1)/n
CROSSREFS
KEYWORD
AUTHOR
Andrew Howroyd, Jan 28 2024
STATUS
approved