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A107472
Composite numbers in sequence A107323.
2
25, 35, 49, 55, 65, 77, 85, 91, 95, 115, 125, 133, 155, 161, 169, 175, 209, 221, 235, 253, 259, 265, 275, 295, 305, 319, 329, 335, 355, 361, 365, 371, 377, 385, 391, 395, 403, 407, 437, 445, 451, 455, 469, 481, 485, 493, 497, 505, 511, 539, 545, 559, 565, 575
OFFSET
1,1
LINKS
MAPLE
a:=proc(n) if ithprime(n) mod 6 = 5 then ithprime(n)+2 elif ithprime(n) mod 6 = 1 then ithprime(n)-2 else 0 fi end: A:=[seq(a(n), n=3..130)]: b:=proc(n) if isprime(A[n])=false then A[n] else fi end: seq(b(m), m=1..nops(A)); # Emeric Deutsch, Jun 19 2005
MATHEMATICA
f[p_] := If[Mod[p, 6] == 5, p + 2, p - 2];
Select[f /@ Prime[Range[3, 200]], CompositeQ] (* Jean-François Alcover, Jun 22 2020 *)
CROSSREFS
Sequence in context: A067793 A287918 A054550 * A193165 A060976 A036320
KEYWORD
nonn
AUTHOR
Leroy Quet, May 27 2005
EXTENSIONS
More terms from Emeric Deutsch, Jun 19 2005
Offset corrected by Robert Israel, Apr 02 2018
STATUS
approved