OFFSET
1,4
COMMENTS
a(n) = 0 for n = 15, 25, 33, 35, 39, 55, 57,… (see A200046).
a(n) = 1 if n prime.
LINKS
Michel Lagneau, Table of n, a(n) for n = 1..1000
EXAMPLE
a(6) = 2 because:
for x = 3, 3^6 + 4^6 == 1(mod 6) and 5^6 == 1(mod 6).
for x = 5, 5^6 + 6^6 == 1 (mod 6) and (7)^6 == 1 (mod 6).
MAPLE
for n from 1 to 100 do:ii:=0:for x from 0 to n-1 do:if x^n+(x+1)^n -(x+2)^n mod n=0 then ii:=ii+1:else fi:od: printf(`%d, `, ii):od:
MATHEMATICA
Array[Function[n, Count[Array[Mod[#^n+(#+1)^n-(#+2)^n, n]&, n, 0], 0]], 84]
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, Nov 14 2011
STATUS
approved