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A239826 Sum of divisors of n that are also suffixes of n in binary representation. 2
1, 2, 4, 4, 6, 8, 8, 8, 10, 12, 12, 16, 14, 16, 19, 16, 18, 20, 20, 24, 22, 24, 24, 32, 26, 28, 31, 32, 30, 38, 32, 32, 34, 36, 36, 40, 38, 40, 43, 48, 42, 44, 44, 48, 51, 48, 48, 64, 50, 52, 55, 56, 54, 62, 56, 64, 58, 60, 60, 76, 62, 64, 74, 64, 66, 68, 68 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Index entries for sequences related to binary expansion of n

EXAMPLE

.   n | divisors       |  . . . in binary          |               a(n)

.  ---+----------------+---------------------------+--------------------

.  10 | 1,2,5,10       |  1,10,101,1010            |  2 + 10     |  12

.  11 | 1,11           |  1,1011                   |  1 + 11     |  12

.  12 | 1,2,3,4,6,12   |  1,10,11,100,110,1100     |  4 + 12     |  16

.  13 | 1,13           |  1,1101                   |  1 + 13     |  14

.  14 | 1,2,7,14       |  1,10,111,1110            |  2 + 14     |  16

.  15 | 1,3,5,15       |  1,11,101,1111            |  1 + 3 + 15 |  19

.  16 | 1,2,4,8,16     |  1,10,100,1000,10000      |  16         |  16

.  17 | 1,17           |  1,10001                  |  1 + 17     |  18

.  18 | 1,2,3,6,9,18   |  1,10,11,110,1001,10010   |  2 + 18     |  20

.  19 | 1,19           |  1,10011                  |  1 + 19     |  20

.  20 | 1,2,4,5,10,20  |  1,10,100,101,1010,10100  |  4 + 20     |  24;

a(63) = 1 + 3 + 7 + 63 = 74;

a(735) = 1 + 3 + 7 + 15 + 735 = 761;

a(4095) = 1 + 3 + 7 + 15 + 63 + 4095 = 4185;

a(185535) = 1 + 3 + 7 + 15 + 31 + 63 + 185535 = 185655.

PROG

(Haskell)

import Data.List (isPrefixOf); import Data.Function (on)

a239826 n = sum $

            filter ((flip isPrefixOf `on` a030308_row) n) $ a027750_row n

-- Reinhard Zumkeller, Mar 27 2014

CROSSREFS

Cf. A030308, A027750, A080942, A000203, A007088.

Sequence in context: A132118 A221952 A007843 * A246601 A288529 A288772

Adjacent sequences:  A239823 A239824 A239825 * A239827 A239828 A239829

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Mar 27 2014

STATUS

approved

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Last modified August 8 21:55 EDT 2022. Contains 356016 sequences. (Running on oeis4.)