A110889 - OEIS

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A110889

Carmichael numbers that are not == 1 mod 12. There are 69 Carmichael numbers out to 2*m+1, m=2*10^6 and all but the above 9 are 1 mod 12.

561, 2465, 8911, 62745, 162401, 656601, 1024651, 1152271, 1909001 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,1`
	LINKS	`Table of n, a(n) for n=1..9.`
	EXAMPLE	`8911=71967=5 mod 12.`
	MAPLE	`with(numtheory); CM:=[]: for z from 1 to 1 do for m from 1 to 2000000 do n:=2*m+1; if not(isprime(n)) and issqrfree(n) then PF:=factorset(n); cmb:=true; for x in PF do if (n-1) mod (x-1) > 0 then cmb:=false fi od; if cmb then CM:=[op(CM), n]; fi; fi; #not od; #m od; #z select(proc(z) not(z mod 12 = 1) end, CM);`
	CROSSREFS	`Cf. A002997.` `Sequence in context: A135720 A217465 A097130 * A205947 A207080 A063400` `Adjacent sequences: A110886 A110887 A110888 * A110890 A110891 A110892`
	KEYWORD	`nonn`
	AUTHOR	`Walter Kehowski, Sep 20 2005`
	STATUS	`approved`

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Last modified June 19 05:13 EDT 2013. Contains 226390 sequences.