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 A032810 Numbers using only digits 2 and 3. 28
 2, 3, 22, 23, 32, 33, 222, 223, 232, 233, 322, 323, 332, 333, 2222, 2223, 2232, 2233, 2322, 2323, 2332, 2333, 3222, 3223, 3232, 3233, 3322, 3323, 3332, 3333, 22222, 22223, 22232, 22233, 22322, 22323, 22332, 22333, 23222, 23223 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Identical to A007931 with substitution of digits 2 -> 3, 1 -> 2, i.e., application of the function A048379 or A256079(n) = n + A002275(A055642(n)). - M. F. Hasler, Mar 21 2015 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 FORMULA a(n) = f(n+1, 0) with f(n, x) = if n=1 then A004086(x) else f(floor(n/2), 10*x + 2 + n mod 2). - Reinhard Zumkeller, Sep 06 2008 a(n) is Theta(n^(log_2 10)); there are about n^(log_10 2) members of this sequence up to n. - Charles R Greathouse IV, Mar 18 2010 a(n) = A007931(n) + A002275(A000523(n+1)). A055642(a(n)) = A000523(n+1). - M. F. Hasler, Mar 21 2015 MATHEMATICA Flatten[Table[FromDigits[#, 10]&/@Tuples[{2, 3}, n], {n, 5}]] (* Vincenzo Librandi, May 27 2012 *) PROG (MAGMA) [n: n in [1..24000] | Set(Intseq(n)) subset {2, 3}]; // Vincenzo Librandi, May 27 2012 (MAGMA) [n eq 1 select 2 else IsOdd(n) select 10*Self(Floor(n/2))+2 else Self(n-1)+1: n in [1..40]]; // Bruno Berselli, May 27 2012 (Haskell) a032810 = f 0 . (+ 1) where    f y 1 = a004086 y    f y x = f (10 * y + m + 2) x' where (x', m) = divMod x 2 -- Reinhard Zumkeller, Mar 18 2015 (PARI) A032810(n)=vector(#n=binary(n+1)[2..-1], i, 10^(#n-i))*n~+10^#n\9*2 \\ M. F. Hasler, Mar 26 2015 CROSSREFS Cf. A020458, A143967, A248907 (permutation). Cf. A032804-A032816 (in other bases), A007088 (digits 0 & 1), A007931 (digits 1 & 2), A032834 (digits 3 & 4), A256290 (digits 4 & 5), A256291 (digits 5 & 6), A256292 (digits 6 & 7), A256340 (digits 7 & 8), A256341 (digits 8 & 9). Sequence in context: A084797 A163902 A154865 * A248907 A062921 A298470 Adjacent sequences:  A032807 A032808 A032809 * A032811 A032812 A032813 KEYWORD nonn,base,easy AUTHOR STATUS approved

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Last modified August 18 08:57 EDT 2019. Contains 326077 sequences. (Running on oeis4.)