A170988 - OEIS

%I #13 Mar 09 2023 09:59:46

%S 0,1,4,2,2,4,1,49,64,81,93,58,74,85,196,225,207,233,212,242,218,98,

%T 141,137,128,121,116,106,98,106,116,121,128,137,141,196,218,242,212,

%U 233,207,225,49,85,74,58,93,81,64,2401,2500,2601,2697,2452,2552,2647,3136,3249

%N Carryless product n X n in base 7.

%H Seiichi Manyama, <a href="/A170988/b170988.txt">Table of n, a(n) for n = 0..2400</a>

%H David Applegate, Marc LeBrun and N. J. A. Sloane, <a href="http://neilsloane.com/doc/carry1.pdf">Carryless Arithmetic (I): The Mod 10 Version</a>.

%H <a href="/index/Ca#CARRYLESS">Index entries for sequences related to carryless arithmetic</a>

%o (PARI) a(n) = fromdigits(Vec(Pol(digits(n, 7))^2)%7, 7); \\ _Seiichi Manyama_, Mar 09 2023

%Y For bases 2 through 10 see A000695, A169999, A170985-A170990 and A059729.

%K nonn,base,look

%O 0,3

%A _N. J. A. Sloane_, Aug 29 2010