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Array T(n, k), n, k >= 0, read by antidiagonals; lunar multiplication table for the primorial base.
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%I #13 Apr 08 2021 10:49:22

%S 0,0,0,0,1,0,0,2,2,0,0,3,6,3,0,0,2,8,8,2,0,0,3,6,9,6,3,0,0,6,8,8,8,8,

%T 6,0,0,7,30,9,12,9,30,7,0,0,8,32,36,14,14,36,32,8,0,0,9,36,39,30,15,

%U 30,39,36,9,0,0,8,38,38,32,36,36,32,38,38,8,0

%N Array T(n, k), n, k >= 0, read by antidiagonals; lunar multiplication table for the primorial base.

%C To compute T(n, k):

%C - write the primorial base representations of n and of k on two lines, right aligned,

%C - to "multiply" two digits: take the smallest,

%C - to "add" two digits: take the largest,

%C - for example, for T(9, 10):

%C 9 -> 1 1 1

%C 10 -> x 1 2 0

%C -------

%C 0 0 0

%C 1 1 1

%C + 1 1 1

%C -----------

%C 1 1 1 1 0 -> 248 = T(9, 10)

%C See A343044 for the corresponding addition table.

%H Rémy Sigrist, <a href="/A343046/b343046.txt">Table of n, a(n) for n = 0..10010</a>

%H Rémy Sigrist, <a href="/A343046/a343046.gp.txt">PARI program for A343046</a>

%H <a href="/index/Di#dismal">Index entries for sequences related to dismal (or lunar) arithmetic</a>

%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>

%F T(n, k) = T(k, n).

%F T(m, T(n, k)) = T(T(m, n), k).

%F T(n, 0) = 0.

%F T(n, 1) = A328841(n).

%F T(n, n) = A343047(n).

%e Array T(n, k) begins:

%e n\k| 0 1 2 3 4 5 6 7 8 9 10 11 12

%e ---+---------------------------------------------------------

%e 0| 0 0 0 0 0 0 0 0 0 0 0 0 0

%e 1| 0 1 2 3 2 3 6 7 8 9 8 9 6 -> A328841

%e 2| 0 2 6 8 6 8 30 32 36 38 36 38 30

%e 3| 0 3 8 9 8 9 36 39 38 39 38 39 36

%e 4| 0 2 6 8 12 14 30 32 36 38 42 44 60

%e 5| 0 3 8 9 14 15 36 39 38 39 44 45 66

%e 6| 0 6 30 36 30 36 210 216 240 246 240 246 210

%e 7| 0 7 32 39 32 39 216 217 248 249 248 249 216

%e 8| 0 8 36 38 36 38 240 248 246 248 246 248 240

%e 9| 0 9 38 39 38 39 246 249 248 249 248 249 246

%e 10| 0 8 36 38 42 44 240 248 246 248 252 254 270

%e 11| 0 9 38 39 44 45 246 249 248 249 254 255 276

%e 12| 0 6 30 36 60 66 210 216 240 246 270 276 420

%o (PARI) See Links section.

%Y Cf. A087062, A235168, A328841, A343042, A343044, A343047.

%K nonn,base,tabl

%O 0,8

%A _Rémy Sigrist_, Apr 05 2021