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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A329332 Table of powers of squarefree numbers, powers of A019565(n) in increasing order in row n. Square array A(n,k) n >= 0, k >= 0 read by descending antidiagonals.

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%I A329332 #25 Dec 03 2022 05:43:00
%S A329332 1,1,1,1,2,1,1,4,3,1,1,8,9,6,1,1,16,27,36,5,1,1,32,81,216,25,10,1,1,
%T A329332 64,243,1296,125,100,15,1,1,128,729,7776,625,1000,225,30,1,1,256,2187,
%U A329332 46656,3125,10000,3375,900,7,1,1,512,6561,279936,15625,100000,50625,27000,49,14
%N A329332 Table of powers of squarefree numbers, powers of A019565(n) in increasing order in row n. Square array A(n,k) n >= 0, k >= 0 read by descending antidiagonals.
%C A329332 The A019565 row order gives the table neat relationships with A003961, A003987, A059897, A225546, A319075 and A329050. See the formula section.
%C A329332 Transposition of this table, that is reflection about its main diagonal, has subtle symmetries. For example, consider the unique factorization of a number into powers of distinct primes. This can be restated as factorization into numbers from rows 2^n (n >= 0) with no more than one from each row. Reflecting about the main diagonal, this factorization becomes factorization (of a related number) into numbers from columns 2^k (k >= 0) with no more than one from each column. This is also unique and is factorization into powers of squarefree numbers with distinct exponents that are powers of two. See the example section.
%F A329332 A(n,k) = A019565(n)^k.
%F A329332 A(k,n) = A225546(A(n,k)).
%F A329332 A(n,2k) = A000290(A(n,k)) = A(n,k)^2.
%F A329332 A(2n,k) = A003961(A(n,k)).
%F A329332 A(n,2k+1) = A(n,2k) * A(n,1).
%F A329332 A(2n+1,k) = A(2n,k) * A(1,k).
%F A329332 A(A003987(n,m), k) = A059897(A(n,k), A(m,k)).
%F A329332 A(n, A003987(m,k)) = A059897(A(n,m), A(n,k)).
%F A329332 A(2^n,k) = A319075(k,n+1).
%F A329332 A(2^n, 2^k) = A329050(n,k).
%F A329332 A(n,k) = A297845(A(n,1), A(1,k)) = A306697(A(n,1), A(1,k)), = A329329(A(n,1), A(1,k)).
%F A329332 Sum_{n>=0} 1/A(n,k) = zeta(k)/zeta(2*k), for k >= 2. - _Amiram Eldar_, Dec 03 2022
%e A329332 Square array A(n,k) begins:
%e A329332 n\k |  0   1     2      3        4          5           6             7
%e A329332 ----+------------------------------------------------------------------
%e A329332    0|  1   1     1      1        1          1           1             1
%e A329332    1|  1   2     4      8       16         32          64           128
%e A329332    2|  1   3     9     27       81        243         729          2187
%e A329332    3|  1   6    36    216     1296       7776       46656        279936
%e A329332    4|  1   5    25    125      625       3125       15625         78125
%e A329332    5|  1  10   100   1000    10000     100000     1000000      10000000
%e A329332    6|  1  15   225   3375    50625     759375    11390625     170859375
%e A329332    7|  1  30   900  27000   810000   24300000   729000000   21870000000
%e A329332    8|  1   7    49    343     2401      16807      117649        823543
%e A329332    9|  1  14   196   2744    38416     537824     7529536     105413504
%e A329332   10|  1  21   441   9261   194481    4084101    85766121    1801088541
%e A329332   11|  1  42  1764  74088  3111696  130691232  5489031744  230539333248
%e A329332   12|  1  35  1225  42875  1500625   52521875  1838265625   64339296875
%e A329332 Reflection of factorization about the main diagonal: (Start)
%e A329332 The canonical (prime power) factorization of 864 is 2^5 * 3^3 = 32 * 27. Reflecting the factors about the main diagonal of the table gives us 10 * 36 = 10^1 * 6^2 = 360. This is the unique factorization of 360 into powers of squarefree numbers with distinct exponents that are powers of two.
%e A329332 Reflection about the main diagonal is given by the self-inverse function A225546(.). Clearly, all positive integers are in the domain of A225546, whether or not they appear in the table. It is valid to start from 360, observe that A225546(360) = 864, then use 864 to derive 360's factorization into appropriate powers of squarefree numbers as above.
%e A329332 (End)
%Y A329332 The range of values is A072774.
%Y A329332 Rows (abbreviated list): A000079(1), A000244(2), A000400(3), A000351(4), A011557(5), A001024(6), A009974(7), A000420(8), A001023(9), A009965(10), A001020(16), A001022(32), A001026(64).
%Y A329332 A019565 is column 1, A334110 is column 2, and columns that are sorted in increasing order (some without the 1) are: A005117(1), A062503(2), A062838(3), A113849(4), A113850(5), A113851(6), A113852(7).
%Y A329332 Other subtables: A182944, A319075, A329050.
%Y A329332 Re-ordered subtable of A297845, A306697, A329329.
%Y A329332 A000290, A003961, A003987, A059897 and A225546 are used to express relationships between terms of this sequence.
%Y A329332 Cf. A285322.
%K A329332 nonn,tabl
%O A329332 0,5
%A A329332 _Peter Munn_, Nov 10 2019