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%I #13 Feb 01 2021 00:15:13
%S 0,1,3,2,4,6,9,5,7,27,10,12,8,28,30,11,13,15,29,31,33,18,14,16,36,32,
%T 34,54,19,21,17,37,39,35,55,57,20,22,24,38,40,42,56,58,60,81,23,25,45,
%U 41,43,63,59,61,243,82,84,26,46,48,44,64,66,62,244,246,83,85,87,47,49
%N Square array A, where entry A(y,x) has the ternary digits of x interleaved with the ternary digits of y, converted back to decimal. Listed by antidiagonals: A(0,0), A(0,1), A(1,0), A(0,2), A(1,1), A(2,0), ...
%H Antti Karttunen, <a href="/A163328/b163328.txt">Table of n, a(n) for n = 0..3320</a>
%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F a(n) = A037314(A025581(n)) + 3*A037314(A002262(n))
%F a(n) = A163327(A163330(n)).
%e From _Kevin Ryde_, Oct 06 2020: (Start)
%e Array A(y,x) read by downwards antidiagonals, so 0, 1,3, 2,4,6, etc.
%e x=0 1 2 3 4 5 6 7 8
%e +--------------------------------------
%e y=0 | 0, 1, 2, 9, 10, 11, 18, 19, 20,
%e 1 | 3, 4, 5, 12, 13, 14, 21, 22,
%e 2 | 6, 7, 8, 15, 16, 17, 24,
%e 3 | 27, 28, 29, 36, 37, 38,
%e 4 | 30, 31, 32, 39, 40,
%e 5 | 33, 34, 35, 42,
%e 6 | 54, 55, 56,
%e 7 | 57, 58,
%e 8 | 60,
%e (End)
%o (Scheme) (define (A163328 n) (+ (A037314 (A025581 n)) (* 3 (A037314 (A002262 n)))))
%o (PARI) A(y,x) = 3*fromdigits(digits(y,3),9) + fromdigits(digits(x,3),9); \\ _Kevin Ryde_, Oct 06 2020
%Y Inverse: A163329. Transpose: A163330. Cf. A037314 (row y=0), A208665 (column x=0)
%Y Cf. A054238 is an analogous sequence for binary. Cf. A007089, A163327, A163332, A163334.
%K nonn,tabl,base
%O 0,3
%A _Antti Karttunen_, Jul 29 2009
%E Edited by _Charles R Greathouse IV_, Nov 01 2009
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