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A322083 Square array A(n,k), n >= 1, k >= 0, read by antidiagonals: A(n,k) = Sum_{d|n} (-1)^(n/d+d)*d^k. 16

%I #22 Jan 07 2024 15:52:07

%S 1,1,-2,1,-3,2,1,-5,4,-1,1,-9,10,-3,2,1,-17,28,-13,6,-4,1,-33,82,-57,

%T 26,-12,2,1,-65,244,-241,126,-50,8,0,1,-129,730,-993,626,-252,50,-3,3,

%U 1,-257,2188,-4033,3126,-1394,344,-45,13,-4,1,-513,6562,-16257,15626,-8052,2402,-441,91,-18,2

%N Square array A(n,k), n >= 1, k >= 0, read by antidiagonals: A(n,k) = Sum_{d|n} (-1)^(n/d+d)*d^k.

%C For each k, the k-th column sequence (T(n,k))(n>=1) is a multiplicative function of n, equal to (-1)^(n+1)*(Id_k * 1) in the notation of the Bala link. - _Peter Bala_, Mar 19 2022

%H Andrew Howroyd, <a href="/A322083/b322083.txt">Table of n, a(n) for n = 1..1275</a> (first 50 antidiagonals)

%H Peter Bala, <a href="/A067856/a067856_1.pdf">A signed Dirichlet product of arithmetical functions</a>

%H <a href="/index/Ge#Glaisher">Index entries for sequences mentioned by Glaisher</a>

%F G.f. of column k: Sum_{j>=1} (-1)^(j+1)*j^k*x^j/(1 + x^j).

%e Square array begins:

%e 1, 1, 1, 1, 1, 1, ...

%e -2, -3, -5, -9, -17, -33, ...

%e 2, 4, 10, 28, 82, 244, ...

%e -1, -3, -13, -57, -241, -993, ...

%e 2, 6, 26, 126, 626, 3126, ...

%e -4, -12, -50, -252, -1394, -8052, ...

%t Table[Function[k, Sum[(-1)^(n/d+d) d^k, {d, Divisors[n]}]][i - n], {i, 0, 11}, {n, 1, i}] // Flatten

%t Table[Function[k, SeriesCoefficient[Sum[(-1)^(j + 1) j^k x^j/(1 + x^j), {j, 1, n}], {x, 0, n}]][i - n], {i, 0, 11}, {n, 1, i}] // Flatten

%t f[p_, e_, k_] := If[k == 0, e + 1, (p^(k*e + k) - 1)/(p^k - 1)]; f[2, e_, k_] := If[k == 0, e - 3, -((2^(k - 1) - 1)*2^(k*e + 1) + 2^(k + 1) - 1)/(2^k - 1)]; T[1, k_] = 1; T[n_, k_] := Times @@ (f[First[#], Last[#], k] & /@ FactorInteger[n]); Table[T[n - k, k], {n, 1, 11}, {k, n - 1, 0, -1}] // Flatten (* _Amiram Eldar_, Nov 22 2022 *)

%o (PARI) T(n,k)={sumdiv(n, d, (-1)^(n/d+d)*d^k)}

%o for(n=1, 10, for(k=0, 8, print1(T(n, k), ", ")); print); \\ _Andrew Howroyd_, Nov 26 2018

%Y Columns k=0..12 give A228441, A109506, A321558, A321559, A321560, A321561, A321562, A321563, A321564, A321565, A321807, A321808, A321809.

%Y Cf. A109974, A279394, A279396, A285425, A322081, A322082, A322084.

%K sign,tabl

%O 1,3

%A _Ilya Gutkovskiy_, Nov 26 2018

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Last modified April 23 18:16 EDT 2024. Contains 371916 sequences. (Running on oeis4.)