A176892 - OEIS

%I #9 Jul 16 2015 18:59:07

%S 2,3,23,33,223,323,233,333,2223,3223,2323,3323,2233,3233,2333,3333,

%T 22223,32223,23223,33223,22323,32323,23323,33323,22233,32233,23233,

%U 33233,22333,32333,23333,33333,222223,322223,232223,332223,223223

%N Decimal representation of the reverted binary representation of n followed by digits substitution 0->2, 1->3.

%C Revert the digits of A007088(n), preserving zeros, and increase each digit by 2 (add the repunit A002276 with the same number of digits).

%H Reinhard Zumkeller, <a href="/A176892/b176892.txt">Table of n, a(n) for n = 0..10000</a>

%e n=10 is A007088(10)= 1010 in binary, reverted 0101. Adding 2222 generates a(10)=2323.

%t Table[Sum[Table[((IntegerDigits[ n, 2]) /. 0 -> 2) /. 1 -> 3, {n, 0, 50}][[n]][[m]]*10^(m - 1),

%t {m, 1, Length[Table[((IntegerDigits[n, 2]) /. 0 -> 2) /. 1 -> 3, {n, 0, 50}][[n]]]}], {n, 1, 51}]

%o (Haskell)

%o import Data.List (unfoldr); import Data.Tuple (swap)

%o a176892 0 = 2a176892 n = foldl (\v d -> 10 * v + d + 2) 0 $

%o    unfoldr (\x -> if x == 0 then Nothing else Just $ swap $ divMod x 2) n

%o -- _Reinhard Zumkeller_, Jul 16 2015

%Y Cf. A007088, A002276, A032810.

%K nonn,base,easy

%O 0,1

%A _Roger L. Bagula_, Apr 28 2010