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.

Showing 1-5 of 5 results.

A221369 A two-digit Look-and-Say sequence starting with 13: each term summarizes the increasing two-digit substrings of the previous term.

Original entry on oeis.org

13, 113, 111113, 411113, 311113141, 311113114231141, 511113214123331141142, 511112113314121123131132233241142151, 711312313214115321122223124331232233241142251, 411412213214115221522423224125431432233241142143151153171
Offset: 0

Views

Author

Reinhard Zumkeller, Jan 13 2013

Keywords

Comments

a(22) is the first term containing a zero; this is due to the fact that a(21) is the first term having exactly 10 occurrences of a two-digit number, namely 10 x 42.

Examples

			a(0) = 11: 1 x 13 --> a(1) = 113;
a(1) = 113: 1 x 11 and 1 x 13 --> a(2) = 111113;
a(2) = 111113: 4 x 11 and 1 x 13 --> a(3) = 411113;
a(3) = 411113: 3 x 11, 1 x 13 and 1 x 41 --> a(4) = 311113141.
		

Crossrefs

Cf. A209234 (start=10), A209233 (start=11), A221368 (start=12), A221372 (start=19), A221373 (start=99).

Programs

  • Haskell
    -- See Link.

A209233 A two-digit Look-and-Say sequence starting with 11: each term summarizes the increasing two-digit substrings of the previous term.

Original entry on oeis.org

11, 111, 211, 111121, 311112121, 311212221131, 211212113221222231, 211312113421422123131132, 311212413114421122123331132134242, 411412313114421122123224331132233134141342144, 411312413414321322323124431232233234441242143244
Offset: 0

Views

Author

Reinhard Zumkeller, Jan 13 2013

Keywords

Comments

a(16) is the first term containing a zero; this is due to the fact that a(15) is the first term having exactly 10 occurrences of a two-digit number, namely 10 x 31.

Examples

			a(0) = 11: 1 x 11 --> a(1) = 111;
a(1) = 111: 2 x 11 --> a(2) = 211;
a(2) = 211: 1 x 11 and 1 x 21 --> a(3) = 111121;
a(3) = 111121: 3 x 11, 1 x 12 and 1 x 21 --> a(4) = 311112121.
		

Crossrefs

Cf. A209234 (start=10), A221368 (start=12), A221369 (start=13), A221372 (start=19), A221373 (start=99).

Programs

  • Haskell
    -- See Link.

A221368 A two-digit Look-and-Say sequence starting with 12: each term summarizes the increasing two-digit substrings of the previous term.

Original entry on oeis.org

12, 112, 111112, 411112, 311112141, 311112114121131141, 611212113214221231241, 211412113114421122123124131132141142161, 611412313414116621122123124331132341242144161, 411512213314216321122323224331132133234541142143144261162166
Offset: 0

Views

Author

Reinhard Zumkeller, Jan 13 2013

Keywords

Comments

a(36) is the first term containing a zero; this is due to the fact that a(35) is the first term having exactly 10 occurrences of a two-digit number, namely 10 x 42.

Examples

			a(0) = 12: 1 x 12 --> a(1) = 112;
a(1) = 112: 1 x 11 ana 1 x 12 --> a(2) = 111112;
a(2) = 111112: 4 x 11 and 1 x 12 --> a(4) = 411112;
a(3) = 411112: 3 x 11, 1 x 12 and 1 x 41 --> a(4) = 311112141.
		

Crossrefs

Cf. A209234 (start=10), A209233 (start=11), A221369 (start=13), A221372 (start=19), A221373 (start=99).

Programs

  • Haskell
    -- See Link.

A221372 A two-digit Look-and-Say sequence starting with 19: each term summarizes the increasing two-digit substrings of the previous term.

Original entry on oeis.org

19, 119, 111119, 411119, 311119141, 311114119131141191, 611113214219231241291, 311212113114119221123124129131132141142161191192, 911512313314116319521122123124129431132341142161291292
Offset: 0

Views

Author

Reinhard Zumkeller, Jan 13 2013

Keywords

Comments

a(16) is the first term containing a zero; this is due to the fact that a(15) is the first term having exactly 10 occurrences of a two-digit number, namely 10 x 51.

Examples

			a(0) = 19: 1 x 19 --> a(1) = 119;
a(1) = 119: 1 x 11 and 1 x 19 --> a(2) = 111119;
a(2) = 111119: 4 x 11 and 1 x 19 --> a(3) = 411119;
a(3) = 411119: 3 x 11, 1 x 19 and 1 x 41 --> a(4) = 311119141.
		

Crossrefs

Cf. A209234 (start=10), A209233 (start=11), A221368 (start=12), A221369 (start=13), A221373 (start=99).

Programs

  • Haskell
    -- See Link.

A221373 A two-digit Look-and-Say sequence starting with 99: each term summarizes the increasing two-digit substrings of the previous term.

Original entry on oeis.org

99, 199, 119199, 111219191199, 311112319121291199, 411312219121123129231291199, 311512113219221122223229331141291192199, 511312113114115319421522123229231232133141151191292193199, 611412313214315419521222323229631232133241142251152153191292193194199
Offset: 0

Views

Author

Reinhard Zumkeller, Jan 13 2013

Keywords

Comments

a(22) is the first term containing a zero; this is due to the fact that a(21) is the first term having exactly 10 occurrences of a two-digit number, namely 10 x 32.

Examples

			a(0) = 11: 1x99 --> a(1)=199;
a(1) = 199: 1x19 and 1x99 --> a(2)=119199;
a(2) = 119199: 1x11, 2x19, 1x91 and 1x99 --> a(3)=111219191199;
a(3) = 111219191199: 3x11, 1x12, 3x19, 1x21, 2x91 and 1x99 --> a(4)=311112319121291199.
		

Crossrefs

Cf. A209234 (start=10), A209233 (start=11), A221368 (start=12), A221369 (start=13), A221372 (start=19).

Programs

  • Haskell
    -- See Link.
Showing 1-5 of 5 results.