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Search: a076243 -id:a076243
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Remainder when 2nd order prime pp(n) = A006450(n) is divided by n-th prime = A000040(n).
+10
6
1, 2, 1, 3, 9, 2, 8, 10, 14, 22, 3, 9, 15, 19, 23, 29, 41, 39, 63, 69, 2, 6, 16, 16, 24, 42, 48, 52, 54, 52, 74, 84, 88, 102, 114, 122, 134, 152, 156, 166, 168, 1, 7, 13, 19, 23, 31, 71, 71, 73, 73, 65, 77, 91, 79, 91, 109, 115, 125, 137, 149, 155, 185, 197, 203, 197, 235
OFFSET
1,2
LINKS
FORMULA
a(n) = prime^2(n) mod prime(n) = A006450(n) mod A000040(n).
EXAMPLE
a(4) = 3 since prime(prime(4)) (mod prime(4)) = prime(7) (mod 7) = 17 (mod 7) = 3. - Michael De Vlieger, Mar 25 2017
MAPLE
a:= n-> (p-> irem(ithprime(p), p))(ithprime(n)):
seq(a(n), n=1..70); # Alois P. Heinz, Oct 09 2015
MATHEMATICA
Table[Mod @@ Map[Nest[Prime, n, #] &, {2, 1}], {n, 65}] (* Michael De Vlieger, Mar 25 2017 *)
PROG
(PARI) a(n) = prime(prime(n)) % prime(n); \\ Michel Marcus, Mar 25 2017
KEYWORD
nonn,look
AUTHOR
Labos Elemer, Oct 08 2002
STATUS
approved
Remainder when 2nd order prime pp(n)=A006450(n) is divided by n.
+10
3
0, 1, 2, 1, 1, 5, 3, 3, 2, 9, 6, 1, 10, 9, 1, 1, 5, 13, 8, 13, 10, 5, 17, 5, 9, 1, 23, 27, 19, 17, 27, 3, 14, 15, 19, 13, 31, 17, 16, 31, 38, 37, 35, 27, 31, 21, 28, 17, 12, 47, 43, 43, 39, 31, 26, 45, 13, 1, 17, 23, 17, 53, 11, 15, 1, 53, 10, 25, 64, 41, 38, 41, 68, 33, 59, 63, 65
OFFSET
1,3
LINKS
FORMULA
a(n) = A006450(n) mod n.
MATHEMATICA
Table[Mod[Prime[Prime[n]], n], {n, 100}] (* Vincenzo Librandi, Jul 10 2017 *)
PROG
(PARI) a(n) = prime(prime(n)) % n; \\ Michel Marcus, Jul 09 2017
(Magma) [NthPrime(NthPrime(n)) mod(n): n in [1..100]]; // Vincenzo Librandi, Jul 10 2017
KEYWORD
nonn
AUTHOR
Labos Elemer, Oct 08 2002
STATUS
approved
Remainder when 3rd order prime A038580(n) is divided by n-th prime=A000040(n).
+10
3
1, 2, 1, 3, 6, 10, 5, 8, 17, 19, 27, 31, 38, 35, 28, 39, 17, 17, 10, 38, 68, 63, 13, 55, 48, 4, 74, 100, 37, 29, 47, 121, 115, 136, 105, 28, 128, 109, 159, 90, 114, 31, 151, 4, 86, 108, 81, 147, 149, 189, 185, 119, 231, 166, 88, 238, 197, 233, 64, 186, 258, 111, 128, 260
OFFSET
1,2
LINKS
FORMULA
a(n) = Mod[A038580(n), A000040(n)]
MATHEMATICA
Table[Mod[Prime[Prime[Prime[n]]], Prime[n]], {n, 70}] (* Harvey P. Dale, Sep 28 2013 *)
KEYWORD
nonn,less
AUTHOR
Labos Elemer, Oct 08 2002
STATUS
approved

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