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 A179899 Integers of the form A179896(n)/A141468(n+1). 2
 0, 12, 21, 30, 36, 39, 48, 51, 57, 66, 72, 75, 81, 84, 93, 96, 102, 111, 114, 120, 126, 129, 135, 138, 141, 147, 156, 165, 171, 174, 177, 180, 183, 186, 192, 198, 201, 210, 213, 216, 219, 228, 231, 237, 240, 246, 252, 255, 261, 264, 273, 276, 279, 282, 291 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Nathaniel Johnston, Table of n, a(n) for n = 1..10000 EXAMPLE 0 = 0/1, 12 = 108/9, 21 = 315/15, 30 = 630/21, 36 = 900/25 and so on. MAPLE ithnonprime := proc(n)local k: option remember: if(n=1)then return 1: else k := procname(n-1)+1: while true do if(not isprime(k))then return k fi: k:=k+1: od: fi: end: A179899ind := proc(n) option remember: local k: if(n=1)then return 1:fi: for k from procname(n-1)+1 do if(ithnonprime(k) mod 2 <> 0)then return k: fi: od: end: A179899 := proc(n) return 3*(ithnonprime(A179899ind(n))-1)/2: end: seq(A179899(n), n=1..55); # Nathaniel Johnston, May 05 2011 CROSSREFS Cf. A000040, A179545, A179896. Sequence in context: A199981 A274347 A316266 * A085926 A071263 A241503 Adjacent sequences:  A179896 A179897 A179898 * A179900 A179901 A179902 KEYWORD easy,nonn AUTHOR Odimar Fabeny, Jul 31 2010 EXTENSIONS More terms from Odimar Fabeny, Aug 12 2010 Definition rephrased by R. J. Mathar, Sep 01 2010 STATUS approved

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Last modified October 17 12:13 EDT 2019. Contains 328111 sequences. (Running on oeis4.)