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.

Previous Showing 11-13 of 13 results.

A273665 a(0) = 0; for n >= 1: if n = A153880(k) for some k, then a(n) = 2*a(k), otherwise, n = A273670(h) for some h, and a(n) = 1 + 2*a(h).

Original entry on oeis.org

0, 1, 2, 3, 5, 7, 4, 11, 6, 15, 9, 23, 10, 13, 14, 31, 19, 47, 21, 27, 29, 63, 39, 95, 8, 43, 22, 55, 59, 127, 12, 79, 30, 191, 17, 87, 18, 45, 46, 111, 119, 255, 25, 159, 61, 383, 35, 175, 20, 37, 26, 91, 93, 223, 28, 239, 62, 511, 51, 319, 38, 123, 94, 767, 71, 351, 41, 75, 53, 183, 187, 447, 42, 57, 54, 479, 125, 1023, 58
Offset: 0

Views

Author

Antti Karttunen, May 30 2016

Keywords

Links

Crossrefs

Inverse: A273666.
Cf. A153880, A225901, A257680, A266193, A273663, A273670.
Related or similar permutations: A255565, A273667.

Formula

a(0) = 0; for n >= 1: if A257680(A225901(n)) = 0 [i.e., n is one of the terms of A153880], then a(n) = 2*a(A266193(n)), otherwise [when n is one of the terms of A273670], a(n) = 1 + 2*a(A273663(n)).

A266123 Decrement by 1 all digits > 1 in factorial base representation of n and then shift it one digit right.

Original entry on oeis.org

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

Views

Author

Antti Karttunen, Dec 23 2015

Keywords

Examples

			   n     A007623(n)  [subtract 1 from digits > 1     a(n)
       [in factorial  then shift one digit right]  [reinterpret
             base]                                  in decimal]
    0         0    ->      0                         =  0
    1         1    ->      0                         =  0
    2        10    ->      1                         =  1
    3        11    ->      1                         =  1
    4        20    ->      1                         =  1
    5        21    ->      1                         =  1
    6       100    ->     10                         =  2
    7       101    ->     10                         =  2
    8       110    ->     11                         =  3
    9       111    ->     11                         =  3
   10       120    ->     11                         =  3
   11       121    ->     11                         =  3
   12       200    ->     10                         =  2
   13       201    ->     10                         =  2
   14       210    ->     11                         =  3
   15       211    ->     11                         =  3
   16       220    ->     11                         =  3
   17       221    ->     11                         =  3
   18       300    ->     20                         =  4

Links

Crossrefs

Cf. A007623, A257684, A266193.

A276957 Permutation of natural numbers: a(A153880(n)) = A255411(n), a(A273670(n)) = A256450(n).

Original entry on oeis.org

1, 4, 2, 3, 5, 12, 6, 16, 7, 8, 9, 18, 10, 22, 11, 13, 14, 15, 17, 19, 20, 21, 23, 48, 24, 52, 25, 26, 27, 60, 28, 64, 29, 30, 31, 66, 32, 70, 33, 34, 35, 36, 37, 38, 39, 40, 41, 72, 42, 76, 43, 44, 45, 84, 46, 88, 47, 49, 50, 90, 51, 94, 53, 54, 55, 56, 57, 58, 59, 61, 62, 96, 63, 100, 65, 67, 68, 108, 69, 112, 71, 73
Offset: 1

Views

Author

Antti Karttunen, Sep 22 2016

Keywords

Links

Crossrefs

Inverse: A276958.
Cf. A276950, A255411, A256450, A266193, A273663.
For more recursed variants see: A275845, A275847 & A273667.

Programs

Formula

If A276950(n) = 0, then a(n) = A255411(A266193(n)), otherwise a(n) = A256450(A273663(n)).
Previous Showing 11-13 of 13 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.