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A273650
a(n) = A000594(n) mod n.
7
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 8, 0, 0, 0, 10, 0, 7, 0, 0, 20, 1, 0, 0, 16, 0, 0, 24, 0, 21, 0, 21, 32, 0, 0, 31, 22, 27, 0, 30, 0, 31, 24, 0, 22, 27, 0, 0, 0, 21, 28, 29, 0, 45, 0, 54, 4, 14, 0, 49, 54, 0, 0, 30, 24, 64, 36, 45, 0, 19, 0, 67, 70, 0, 32, 42, 54, 37, 0, 0, 18
OFFSET
1,13
LINKS
FORMULA
a(n) = A000594(n) mod n.
From Amiram Eldar, Jan 08 2025: (Start)
a(A063938(n)) = 0.
abs(a(A295654(n))) = 1. (End)
EXAMPLE
tau(10) mod 10 = (-115920) mod 10 = 0,
tau(11) mod 11 = 534612 mod 11 = 1.
MATHEMATICA
a[n_] := Mod[RamanujanTau[n], n]; Array[a, 100] (* Amiram Eldar, Jan 08 2025 *)
PROG
(PARI) a(n)=ramanujantau(n)%n \\ assumes the GRH; Charles R Greathouse IV, May 27 2016
(Python)
from sympy import divisor_sigma
def A273650(n): return -840*(pow(m:=n+1>>1, 2, n)*(0 if n&1 else pow(m*divisor_sigma(m), 2, n))+(sum(pow(i, 4, n)*divisor_sigma(i)*divisor_sigma(n-i) for i in range(1, m))<<1)) % n # Chai Wah Wu, Nov 08 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 27 2016
STATUS
approved