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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.

A347277 Table T(n,k) read by downward antidiagonals: A quotient belonging to a generalization of Euler's theorem.

Original entry on oeis.org

0, 1, 0, 2, 1, 0, 3, 3, 2, 0, 4, 6, 8, 3, 0, 5, 10, 20, 18, 6, 0, 6, 15, 40, 60, 48, 8, 0, 7, 21, 70, 150, 204, 108, 18, 0, 8, 28, 112, 315, 624, 640, 312, 30, 0, 9, 36, 168, 588, 1554, 2500, 2340, 810, 56, 0, 10, 45, 240, 1008, 3360, 7560, 11160, 8160, 2184, 96, 0
Offset: 1

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Author

Franz Vrabec, Aug 26 2021

Keywords

Comments

The quotient T(n,k) = (k^n - k^(n-phi(n)))/n results from the generalization k^n == k^(n-phi(n)) (mod n) of Euler's theorem (see Sierpiński, p. 243).
The n-th row of the table is equal to the n-th row of A074650 iff n = p^j (p prime, j>=1).

Examples

			T(4,3) = (3^4 - 3^2)/4 = 18.
Square array starts:
  0, 1,   2,   3,    4,    5, ...
  0, 1,   3,   6,   10,   15, ...
  0, 2,   8,  20,   40,   70, ...
  0, 3,  18,  60,  150,  315, ...
  0, 6,  48, 204,  624, 1554, ...
  0, 8, 108, 640, 2500, 7560, ...
		

References

  • W. Sierpiński, Elementary Theory of Numbers, Warszawa, 1964.

Crossrefs

Cf. A074650.

Programs

  • Maple
    with(numtheory):
    T:= proc(n, k) (k^n-k^(n-phi(n)))/n end:
    seq(seq(T(i, 1+d-i), i=1..d), d=1..11);
  • PARI
    T(n,k) = (k^n - k^(n - eulerphi(n)))/n; \\ Jinyuan Wang, Aug 28 2021

Formula

T(n,k) = (k^n - k^(n - phi(n)))/n.

Extensions

More terms from Jinyuan Wang, Aug 28 2021