A193492 -id:A193492 - cp's OEIS frontend

A136414 Put the natural numbers together without spaces and read them two at a time advancing one space each time.

12, 23, 34, 45, 56, 67, 78, 89, 91, 10, 1, 11, 11, 12, 21, 13, 31, 14, 41, 15, 51, 16, 61, 17, 71, 18, 81, 19, 92, 20, 2, 21, 12, 22, 22, 23, 32, 24, 42, 25, 52, 26, 62, 27, 72, 28, 82, 29, 93, 30, 3, 31, 13, 32, 23, 33, 33, 34, 43, 35, 53, 36, 63, 37, 73, 38, 83, 39, 94, 40, 4, 41, 14

Offset: 1

Ben Paul Thurston, Mar 31 2008

a(n) = A162711(n,2) for n>1. - Reinhard Zumkeller, Jul 11 2009

			34 is the third entry because the natural numbers written together look like 1234567891011 and reading them off two at a time produces 12, 23, 34, ...

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

Cf. A001704, A193431, A193492, A193493.

a136414 n = a136414_list !! (n-1)
a136414_list = zipWith (+) (tail a007376_list) $ map (10 *) a007376_list
-- Reinhard Zumkeller, Jul 28 2011

a(n) = 10*A007376(n) + A007376(n+1). - Reinhard Zumkeller, Jul 11 2009

More terms from Reinhard Zumkeller, Jul 11 2009

A193431 Put the natural numbers together without spaces and read them three at a time advancing one space each time.

Original entry on oeis.org

123, 234, 345, 456, 567, 678, 789, 891, 910, 101, 11, 111, 112, 121, 213, 131, 314, 141, 415, 151, 516, 161, 617, 171, 718, 181, 819, 192, 920, 202, 21, 212, 122, 222, 223, 232, 324, 242, 425, 252, 526, 262, 627, 272, 728, 282, 829, 293, 930, 303, 31, 313

Offset: 1

Reinhard Zumkeller, Jul 28 2011

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

Cf. A136414, A193492, A193493.

a193431 n = a193431_list !! (n-1)
a193431_list = f a007376_list where
   f (x:xs'@(x':x'':xs)) = 10*(10*x + x') + x'' : f xs'

Module[{nn=50,d},d=Flatten[IntegerDigits/@Range[nn]];FromDigits/@ Partition[ d,3,1]] (* Harvey P. Dale, Nov 16 2021 *)

a(n) = 10 * (10 * A007376(n) + A007376(n+1)) + A007376(n+2).

A193493 Put the natural numbers together without spaces and read them five at a time advancing one space each time.

Original entry on oeis.org

12345, 23456, 34567, 45678, 56789, 67891, 78910, 89101, 91011, 10111, 1112, 11121, 11213, 12131, 21314, 13141, 31415, 14151, 41516, 15161, 51617, 16171, 61718, 17181, 71819, 18192, 81920, 19202, 92021, 20212, 2122, 21222, 12223, 22232, 22324, 23242, 32425

Offset: 1

Reinhard Zumkeller, Jul 28 2011

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

Cf. A136414, A193431, A193492.

a193493 n = a193493_list !! (n-1)
a193493_list = f a007376_list where
   f xs'@(x:xs) = ((foldl (\u v -> 10*u + v) 0) $ take 5 xs') : f xs

nn=40;With[{tbl=Flatten[IntegerDigits/@Range[nn]]},Table[FromDigits[ Take[tbl,{n,n+4}]],{n,nn}]](* Harvey P. Dale, Aug 10 2011 *)

a(n) = Sum (A007376(n+k)*10^(4-k): 0 <= k <= 4).

cp's OEIS Frontend

A136414 Put the natural numbers together without spaces and read them two at a time advancing one space each time.

Views

Author

Keywords

Comments

Examples

Links

Crossrefs

Programs

Haskell

Formula

Extensions

A193431 Put the natural numbers together without spaces and read them three at a time advancing one space each time.

Views

Author

Keywords

Links

Crossrefs

Programs

Haskell

Mathematica

Formula

A193493 Put the natural numbers together without spaces and read them five at a time advancing one space each time.

Views

Author

Keywords

Links

Crossrefs

Programs

Haskell

Mathematica

Formula