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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.

A353433 Array read by descending antidiagonals: T(n,m) is the number of sequences of length n >= 0 with elements in 0..m-1 such that no iterated difference has a common factor with m >= 1.

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%I A353433 #13 Apr 26 2022 10:22:38
%S A353433 1,1,1,1,1,1,1,2,0,1,1,2,2,0,1,1,4,0,2,0,1,1,2,12,0,2,0,1,1,6,0,28,0,
%T A353433 2,0,1,1,4,30,0,48,0,2,0,1,1,6,0,126,0,60,0,2,0,1,1,4,18,0,444,0,60,0,
%U A353433 2,0,1,1,10,0,54,0,1350,0,52,0,2,0,1
%N A353433 Array read by descending antidiagonals: T(n,m) is the number of sequences of length n >= 0 with elements in 0..m-1 such that no iterated difference has a common factor with m >= 1.
%C A353433 T(n,m) is divisible by T(1,m) = A000010(m) if n >= 1, because if r is coprime to m, the sequence (x_1, ..., x_n) satisfies the conditions if and only if the sequence (r*x_1 mod m, ..., r*x_n mod m) does.
%H A353433 Pontus von Brömssen, <a href="/A353433/a353433.svg">Plot of T(n,7) for 0 <= n <= 200</a>
%F A353433 For fixed n, T(n,m) is multiplicative with T(n,p^e) = T(n,p)*p^(n*(e-1)).
%F A353433 T(n,m) = A353434(n,m) if m is prime.
%F A353433 For each n >= 0, there exists an n-th degree polynomial P such that T(n,m) = P(m) for sufficiently large primes m. For example (for n >= 4, these are empirical observations only):
%F A353433   T(0,m) = 1 for all m >= 1;
%F A353433   T(1,m) = m-1 for all primes m;
%F A353433   T(2,m) = (m-1)*(m-2) for all primes m;
%F A353433   T(3,m) = (m-1)*(m^2-5*m+7) for primes m >= 3;
%F A353433   T(4,m) = (m-1)*(m^3-9*m^2+30*m-38) for primes m >= 5;
%F A353433   T(5,m) = (m-1)*(m^4-14*m^3+81*m^2-235*m+302) for primes m >= 7;
%F A353433   T(6,m) = (m-1)*(m^5-20*m^4+175*m^3-854*m^2+2401*m-3280) for primes m >= 19.
%F A353433 T(n,2) = 0 for n >= 2.
%F A353433 T(n,3) = 2 for n >= 1.
%F A353433 T(n,5) = 48 for n >= 8.
%F A353433 It appears that T(n,7) = T(n+42,7) for n >= 56. (See linked plot.)
%e A353433 Array begins:
%e A353433   n\m| 1  2  3  4  5  6     7  8      9 10
%e A353433   ---+------------------------------------
%e A353433    0 | 1  1  1  1  1  1     1  1      1  1
%e A353433    1 | 1  1  2  2  4  2     6  4      6  4
%e A353433    2 | 1  0  2  0 12  0    30  0     18  0
%e A353433    3 | 1  0  2  0 28  0   126  0     54  0
%e A353433    4 | 1  0  2  0 48  0   444  0    162  0
%e A353433    5 | 1  0  2  0 60  0  1350  0    486  0
%e A353433    6 | 1  0  2  0 60  0  3582  0   1458  0
%e A353433    7 | 1  0  2  0 52  0  8550  0   4374  0
%e A353433    8 | 1  0  2  0 48  0 17364  0  13122  0
%e A353433    9 | 1  0  2  0 48  0 30126  0  39366  0
%e A353433   10 | 1  0  2  0 48  0 44922  0 118098  0
%Y A353433 Cf. A353434, A353435.
%Y A353433 Rows: A000012 (n=0), A000010 (n=1), A061780 (every second term of row n=2).
%Y A353433 Columns: A000012 (m=1), A019590 (m=2), A040000 (m=3), A130706 (m=4 and m=6).
%K A353433 nonn,tabl
%O A353433 0,8
%A A353433 _Pontus von Brömssen_, Apr 21 2022