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A117323 Semiprime(n) modulo prime(n). 0
0, 0, 4, 3, 3, 2, 4, 3, 2, 26, 2, 34, 35, 38, 39, 46, 49, 51, 55, 57, 58, 62, 65, 69, 74, 77, 82, 85, 86, 87, 91, 93, 94, 95, 106, 111, 115, 118, 119, 121, 122, 123, 129, 133, 134, 141, 142, 143, 145, 146, 155, 158, 159, 161, 166, 169, 177, 178, 183, 185, 187 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

After a(14), it is always true that prime(n) > semiprime(n), so that a(n) = semiprime(n).

LINKS

Table of n, a(n) for n=1..61.

FORMULA

a(n) = A001358(n) modulo A000040(n).

EXAMPLE

a(1) = 4 mod 2 = 0.

a(2) = 6 mod 3 = 0

a(3) = 9 mod 5 = 4.

a(4) = 10 mod 7 = 3.

MATHEMATICA

sp = Select[Range[1000], PrimeOmega[#] == 2 &, 100]; Table[ Mod[sp[[i]], Prime[i]], {i, 100}] (* Giovanni Resta, Jun 15 2016 *)

CROSSREFS

Sequence in context: A073871 A120927 A241180 * A016502 A305743 A117691

Adjacent sequences:  A117320 A117321 A117322 * A117324 A117325 A117326

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post, Mar 08 2006

EXTENSIONS

Corrected and extended by Giovanni Resta, Jun 15 2016

STATUS

approved

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Last modified December 17 09:32 EST 2018. Contains 318193 sequences. (Running on oeis4.)