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A175621
a(n) = 2^(composite(n)-4) mod composite(n).
2
1, 4, 0, 5, 4, 4, 2, 8, 0, 4, 16, 11, 14, 16, 2, 10, 5, 8, 4, 0, 17, 30, 23, 4, 24, 20, 16, 4, 12, 32, 6, 16, 8, 14, 26, 40, 22, 13, 16, 29, 22, 16, 8, 32, 0, 2, 4, 52, 35, 64, 40, 28, 23, 20, 30, 4
OFFSET
1,2
LINKS
MAPLE
A175621 := proc(n) local c ; c := A002808(n) ; (2^(c-4)) mod c ; end proc:
seq(A175621(n), n=1..80) ;
MATHEMATICA
Table[PowerMod[2, n-4, n], {n, Select[Range[100], CompositeQ]}] (* Harvey P. Dale, Aug 01 2021 *)
CROSSREFS
Sequence in context: A019906 A197251 A049247 * A016578 A268631 A335775
KEYWORD
nonn,less
AUTHOR
EXTENSIONS
Corrected by D. S. McNeil, Dec 04 2010
STATUS
approved