cp's OEIS Frontend

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.

A119709 Table where n-th row (of A078822(n) terms) contains the distinct nonnegative integers which, when written in binary, are substrings of n written in binary.

Original entry on oeis.org

0, 1, 0, 1, 2, 1, 3, 0, 1, 2, 4, 0, 1, 2, 5, 0, 1, 2, 3, 6, 1, 3, 7, 0, 1, 2, 4, 8, 0, 1, 2, 4, 9, 0, 1, 2, 5, 10, 0, 1, 2, 3, 5, 11, 0, 1, 2, 3, 4, 6, 12, 0, 1, 2, 3, 5, 6, 13, 0, 1, 2, 3, 6, 7, 14, 1, 3, 7, 15, 0, 1, 2, 4, 8, 16, 0, 1, 2, 4, 8, 17, 0, 1, 2, 4, 9, 18, 0, 1, 2, 3, 4, 9, 19, 0, 1, 2, 4, 5, 10
Offset: 0

Views

Author

Leroy Quet, Jun 10 2006

Keywords

Examples

			12 in binary is 1100. Within this binary representation there is 0 (occurring twice), 1 (occurring twice), 10 (= 2 in decimal), 11 (= 3 in decimal), 100 (= 4 in decimal), 110 (= 6 in decimal) and 1100 (= 12 in decimal).
So row 12 = (0,1,2,3,4,6,12).
		

Crossrefs

Programs

  • Haskell
    import Data.List (isInfixOf)
    a119709 n k = a119709_tabf !! n !! k
    a119709_row n = map (foldr (\d v -> v * 2 + toInteger d) 0) $
       filter (`isInfixOf` (a030308_row n)) $ take (n + 1) a030308_tabf
    a119709_tabf = map a119709_row [0..]
    -- Reinhard Zumkeller, Aug 14 2013

Extensions

Extended by Ray Chandler, Mar 13 2010