A059805 Natural numbers written with digits grouped in pairs and leading zeros omitted.

12, 34, 56, 78, 91, 1, 11, 21, 31, 41, 51, 61, 71, 81, 92, 2, 12, 22, 32, 42, 52, 62, 72, 82, 93, 3, 13, 23, 33, 43, 53, 63, 73, 83, 94, 4, 14, 24, 34, 44, 54, 64, 74, 84, 95, 5, 15, 25, 35, 45, 55, 65, 75, 85, 96, 6, 16, 26, 36, 46, 56, 66, 76, 86, 97, 7, 17, 27, 37, 47, 57, 67

Offset: 1

Author

Kazimierz Kurz (kurzk(AT)prokom.pl), Mar 01 2001

Keywords

• easy
• base
• nonn

Links

• Rémy Sigrist, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000027, A087406, A060936, A087407, A087408, A087409, A087075, A087410, A087411.

Cf. A091331, A091332.

Programs

Mathematica

FromDigits /@ Partition[ Flatten[ IntegerDigits[ Table[ n, {n, 1, 77}]]], 2] (* Robert G. Wilson v *)
FromDigits/@Partition[Flatten[IntegerDigits/@Range[100]],2] (* Harvey P. Dale, Feb 13 2025 *)

PARI

{c=0; d=[]; for(n=1, 99, while(#d<2, d=concat(d, digits(c++))); print1(d[1],d[2]", "); d=vecextract(d, "^..2"))} \\ M. F. Hasler, Oct 23 2014

Formula

a(2n-1)*100 + a(2n) = A091332(n); a(2n-1) = floor(A091332(n)/100), a(2n) = (A091332(n) mod 100). - M. F. Hasler, Oct 23 2014

Extensions

More terms from Jason Earls, Mar 24 2001