This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A176892 #9 Jul 16 2015 18:59:07 %S A176892 2,3,23,33,223,323,233,333,2223,3223,2323,3323,2233,3233,2333,3333, %T A176892 22223,32223,23223,33223,22323,32323,23323,33323,22233,32233,23233, %U A176892 33233,22333,32333,23333,33333,222223,322223,232223,332223,223223 %N A176892 Decimal representation of the reverted binary representation of n followed by digits substitution 0->2, 1->3. %C A176892 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 A176892 Reinhard Zumkeller, <a href="/A176892/b176892.txt">Table of n, a(n) for n = 0..10000</a> %e A176892 n=10 is A007088(10)= 1010 in binary, reverted 0101. Adding 2222 generates a(10)=2323. %t A176892 Table[Sum[Table[((IntegerDigits[ n, 2]) /. 0 -> 2) /. 1 -> 3, {n, 0, 50}][[n]][[m]]*10^(m - 1), %t A176892 {m, 1, Length[Table[((IntegerDigits[n, 2]) /. 0 -> 2) /. 1 -> 3, {n, 0, 50}][[n]]]}], {n, 1, 51}] %o A176892 (Haskell) %o A176892 import Data.List (unfoldr); import Data.Tuple (swap) %o A176892 a176892 0 = 2a176892 n = foldl (\v d -> 10 * v + d + 2) 0 $ %o A176892 unfoldr (\x -> if x == 0 then Nothing else Just $ swap $ divMod x 2) n %o A176892 -- _Reinhard Zumkeller_, Jul 16 2015 %Y A176892 Cf. A007088, A002276, A032810. %K A176892 nonn,base,easy %O A176892 0,1 %A A176892 _Roger L. Bagula_, Apr 28 2010