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A266875 Number of partially ordered sets ("posets") with n labeled elements, modulo n. 0
0, 1, 1, 3, 1, 3, 1, 3, 1, 3, 1, 3, 1, 3, 4, 3, 1, 9, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

If n is a prime number, a(n) = 1 because of the fact that A001035(p^k) == 1 mod p for all primes p.

If n is an even number, a(n) is a number of the form 3^k for n <= 19. How is the distribution of terms of the form 3^k in this sequence?

LINKS

Table of n, a(n) for n=1..19.

FORMULA

a(n) = A001035(n) mod n, for n > 0.

a(A000040(n)) = A265847(A000040(n)) - 1, for n > 1.

EXAMPLE

a(4) = A001035(4) mod 4 = 219 mod 4 = 3.

a(5) = A001035(5) mod 5 = 4231 mod 5 = 1.

a(6) = A001035(6) mod 6 = 130023 mod 6 = 3.

a(7) = A001035(7) mod 7 = 6129859 mod 7 = 1.

CROSSREFS

Cf. A001035, A265847.

Sequence in context: A010684 A176040 A125768 * A111742 A178220 A316780

Adjacent sequences:  A266872 A266873 A266874 * A266876 A266877 A266878

KEYWORD

nonn,more

AUTHOR

Altug Alkan, Jan 05 2016

STATUS

approved

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Last modified February 19 07:51 EST 2019. Contains 320309 sequences. (Running on oeis4.)