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All digits even and nonzero.
6

%I #19 Feb 09 2023 02:10:28

%S 2,4,6,8,22,24,26,28,42,44,46,48,62,64,66,68,82,84,86,88,222,224,226,

%T 228,242,244,246,248,262,264,266,268,282,284,286,288,422,424,426,428,

%U 442,444,446,448,462,464,466,468,482,484,486,488,622,624,626,628,642

%N All digits even and nonzero.

%H Reinhard Zumkeller, <a href="/A045926/b045926.txt">Table of n, a(n) for n = 1..10000</a>

%H <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.

%F a(n) = 2 * A084544(n). - _Reinhard Zumkeller_, Jan 01 2013

%o (Haskell)

%o a045926 n = a045926_list !! (n-1)

%o a045926_list = filter (all (`elem` "2468") . show) [2, 4..]

%o -- _Reinhard Zumkeller_, Jan 01 2013

%o (Python)

%o def A045926(n):

%o m = (3*n+1).bit_length()-1>>1

%o return int(''.join((str(((3*n+1-(1<<(m<<1)))//(3<<((m-1-j)<<1))&3)+1) for j in range(m))))<<1 # _Chai Wah Wu_, Feb 08 2023

%Y Cf. A045927, A014261, A014263, A192370.

%K nonn,easy,base

%O 1,1

%A _Felice Russo_

%E More terms from _Patrick De Geest_, Jun 15 1999