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A065860
Remainder when the n-th composite number is divided by n.
8
0, 0, 2, 1, 0, 0, 0, 7, 7, 8, 9, 9, 9, 10, 10, 10, 10, 10, 11, 12, 12, 12, 12, 12, 13, 13, 13, 14, 15, 15, 15, 16, 16, 16, 16, 16, 17, 17, 17, 17, 17, 18, 19, 19, 19, 19, 19, 20, 20, 20, 21, 22, 22, 22, 22, 22, 23, 23, 23, 24, 24, 24, 24, 24, 25, 25, 25, 25, 25, 25, 25, 26, 26
OFFSET
1,3
LINKS
FORMULA
a(n) = A002808(n) mod n.
EXAMPLE
n=100, c(100)=133, a(100)=33.
MATHEMATICA
Module[{nn=100, cmps, len}, cmps=Select[Range[nn], CompositeQ]; len=Length[ cmps]; Mod[#[[1]], #[[2]]]&/@Thread[{cmps, Range[len]}]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Mar 29 2020 *)
PROG
(PARI) Composite(n) = { local(k); k=n + primepi(n) + 1; while (k != n + primepi(k) + 1, k = n + primepi(k) + 1); return(k) } { for (n = 1, 1000, a=Composite(n)%n; write("b065860.txt", n, " ", a) ) } \\ Harry J. Smith, Nov 02 2009
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Nov 26 2001
STATUS
approved