%I #12 Aug 15 2015 15:09:15
%S 1,11,12,2,21,13,3,31,14,4,41,15,5,51,16,6,61,17,7,71,18,8,81,19,9,91,
%T 101,102,22,23,32,24,42,25,52,26,62,27,72,28,82,29,92,201,103,33,34,
%U 43,35,53,36,63,37,73,38,83,39,93,301,104,44,45,54,46,64,47,74,48,84,49,94
%N Smallest natural number not a multiple of 10, not occurring earlier and starting with the end of the previous term.
%C A000030(a(n+1) = A010879(a(n)). - _Reinhard Zumkeller_, Aug 15 2015
%H Reinhard Zumkeller, <a href="/A076654/b076654.txt">Table of n, a(n) for n = 1..8936</a>, all terms < 10000
%p startsWith := proc(n,dig) local nshft ; nshft := n ; while nshft >= 10 do nshft := floor(nshft/10) ; od ; if dig = nshft then RETURN(true) ; else RETURN(false) ; fi ; end: A076654 := proc(nmax) local candid,a; a := [1] ; while nops(a) < nmax do candid := 2 ; while not startsWith(candid,op(-1,a) mod 10) or candid mod 10 = 0 or candid in a do candid := candid+1 ; od ; a := [op(a),candid] ; od ; RETURN(a) ; end: a := A076654(200) : for n from 1 to nops(a) do printf("%d,",op(n,a)) ; od ; # _R. J. Mathar_, Nov 12 2006
%o (Haskell)
%o import Data.List (delete)
%o a076654 n = a076654_list !! (n-1)
%o a076654_list = f a067251_list 1 where
%o f xs z = g xs where
%o g (y:ys) = if a000030 y == mod z 10 then y : f (delete y xs) y else g ys
%o -- _Reinhard Zumkeller_, Aug 15 2015
%Y Cf. A076652, A076653.
%Y Cf. A000030, A010879, A067251.
%K base,nonn
%O 1,2
%A _Amarnath Murthy_, Oct 28 2002
%E More terms from _R. J. Mathar_, Nov 12 2006
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