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.

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A118628 "Say what you see".

Original entry on oeis.org

3, 13, 1113, 3113, 2123, 112213, 312213, 212223, 114213, 31121314, 41122314, 31221324, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314, 21322314
Offset: 1

Views

Author

Parthasarathy Nambi, May 09 2006

Keywords

Examples

			3 = "one three" --> 13
13 = "one one, one three" --> 1113
1113 = "three ones, one three" --> 3113
3113 = "two ones, two threes" --> 2123
		

Crossrefs

Programs

  • Haskell
    import Data.List (group, sort, transpose)
    a118628 n = a118628_list !! (n-1)
    a118628_list = 3 : f [3] :: [Integer] where
       f xs = (read $ concatMap show ys) : f (ys) where
              ys = concat $ transpose [map length zss, map head zss]
              zss = group $ sort xs
    -- Reinhard Zumkeller, Jan 26 2014

Formula

a(n) = 21322314 for n > 12; a(n) = A005151(n) for n > 6. - Reinhard Zumkeller, Jan 26 2014
a(n) = A047842(a(n-1)). - Pontus von Brömssen, Jun 04 2023

A037220 Summarize the previous term!.

Original entry on oeis.org

0, 10, 1011, 1031, 102113, 10311213, 10411223, 1031221314, 1041222314, 1031321324, 1031223314, 1031223314, 1031223314, 1031223314, 1031223314, 1031223314, 1031223314, 1031223314, 1031223314, 1031223314, 1031223314
Offset: 0

Views

Author

Keywords

Examples

			a(0) is given as 0;
a(1) is one zero -> 10;
a(2) is one zero and one one -> 1011;
a(3) is one zero and three ones -> 1031;
a(7) and onward is 1031223314.
		

Crossrefs

Cf. A005151.

Programs

  • Mathematica
    NestList[ FromDigits@ Flatten@ Map[IntegerDigits@ Reverse@# &, Sort@ Tally@ Flatten@ IntegerDigits@#] &, 0, 20] (* Robert G. Wilson v, Nov 28 2019, adapted from code by Michael De Vlieger in A177359 *)

A098153 Summarize the previous term in binary (in increasing order).

Original entry on oeis.org

1, 11, 101, 10101, 100111, 1001001, 1000111, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001, 1101001
Offset: 1

Views

Author

Rick L. Shepherd, Aug 29 2004

Keywords

Comments

Similar to A005151 but uses base 2: Let a(1)=1. Describing a(1) as "one 1" again gives a(2)=11 (same digit string as A005151 and similar sequences), but describing a(2) as "two 1's" gives a(3)=101 when the frequency of digit occurrence is written in binary and followed by the digit counted.

Examples

			Summarizing a(8) = 1101001 in increasing digit order, there are "three 0's, four 1's", so concatenating 11 0 100 1 gives a(9) = 1101001 (=a(10)=a(11)=...).
		

Crossrefs

Cf. A098154 (ternary), A098155 (base 4), A005151 (decimal and digit strings for all other bases b >= 5).

Formula

a(n) = 1101001 for all n >= 8 (see example).

A098154 Summarize the previous term in ternary (in increasing order).

Original entry on oeis.org

1, 11, 21, 1112, 10112, 1010112, 2011112, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122, 1011122
Offset: 1

Views

Author

Rick L. Shepherd, Aug 29 2004

Keywords

Comments

Similar to A005151 but uses base 3: Let a(1)=1. Describing a(1) as "one 1" again gives a(2)=11 (same digit string as A005151 and similar sequences). Likewise, a(3) and a(4) have same digit strings as all but the binary sequence, but describing a(4) as "three 1's, one 2" gives a(5)=10112 when the frequency of digit occurrence is written in ternary and followed by the digit counted.

Examples

			Summarizing a(8) = 1011122 in increasing digit order, there are "one 0, four 1's, two 2s", so concatenating 1 0 11 1 2 2 gives a(9) = 1011122 (=a(10)=a(11)=...).
		

Crossrefs

Cf. A098153 (binary), A098155 (base 4), A005151 (decimal and digit strings for all other bases b >= 5).

Formula

a(n) = 1011122 for all n >= 8 (see example).

A098155 Summarize the previous term in base 4 (in increasing order).

Original entry on oeis.org

1, 11, 21, 1112, 3112, 211213, 312213, 212223, 1110213, 101011213, 201111213, 101112213, 101112213, 101112213, 101112213, 101112213, 101112213, 101112213, 101112213, 101112213, 101112213, 101112213, 101112213, 101112213, 101112213
Offset: 1

Views

Author

Rick L. Shepherd, Aug 29 2004

Keywords

Comments

Let a(1)=1. Describing a(1) as "one 1" again gives a(2)=11 (same digit string as A005151 and similar sequences). Likewise, a(3) through a(8) have the same digit strings as the corresponding terms of A005151, but describing a(8) as "one 1, four 2s, one 3" gives a(9)=1110213 when the frequency of digit occurrence is written in base 4 and followed by the digit counted.

Examples

			Summarizing a(12) = 101112213 in increasing digit order, there are "one 0, five 1's, two 2s, one 3", so concatenating 1 0 11 1 2 2 1 3 gives a(13) = 101112213 (=a(14)=a(15)=...).
		

Crossrefs

Cf. A098153 (binary), A098154 (ternary), A005151 (decimal and digit strings for all other bases b >= 5).

Programs

  • Mathematica
    Nest[Append[#, FromDigits[Flatten@ Map[IntegerDigits[#, 4] & /@ Reverse@ # &, Tally@ Sort@ IntegerDigits@ #[[-1]] ] ]] &, {1}, 24] (* Michael De Vlieger, Jul 15 2020 *)

Formula

a(n) = 101112213 for all n >= 12 (see example).

A138485 Say what you see in previous term, from the right, reporting total number for each digit encountered. Initial term is 1.

Original entry on oeis.org

1, 11, 21, 1112, 1231, 211312, 223113, 232122, 421113, 13311214, 14411223, 13223124, 14322123, 23322114, 14213223, 23322114, 14213223, 23322114, 14213223, 23322114, 14213223, 23322114, 14213223, 23322114, 14213223
Offset: 0

Views

Author

Keywords

Comments

After a while sequence has period 2 -> {23322114,14213223}

Examples

			To get the term after 211312, we say: two 2's, three 1's, one 3's, so 223113.
		

Crossrefs

A138486 Say what you see in previous term, from the right, reporting total number for each digit encountered. Initial term is 2.

Original entry on oeis.org

2, 12, 1211, 3112, 122113, 133122, 222123, 134211, 31121413, 23411412, 22312413, 23211432, 32231421, 21321423, 23321421, 21321423, 23321421, 21321423, 23321421, 21321423, 23321421, 21321423, 23321421, 21321423
Offset: 0

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Author

Keywords

Comments

After a while sequence has period 2 -> {21321423,23321421}

Examples

			To get the term after 122113, we say: one 3's, three 1's, two 2's, so 133122
		

Crossrefs

Extensions

Duplicate term 21321423 removed by Georg Fischer, Sep 18 2023

A138487 Say what you see in previous term, from the right, reporting total number for each digit encountered. Initial term is 3.

Original entry on oeis.org

3, 13, 1311, 3113, 2321, 112213, 133122, 222123, 134211, 31121413, 23411412, 22312413, 23211432, 32231421, 21321423, 23321421, 21321423, 23321421, 21321423, 23321421, 21321423, 23321421, 21321423, 23321421, 21321423
Offset: 0

Views

Author

Keywords

Comments

After a while sequence has period 2 -> {21321423,23321421}

Examples

			To get the term after 112213, we say: one 3's, three 1's, two 2's, so 133122
		

Crossrefs

A138488 Say what you see in previous term, from the right, reporting total number for each digit encountered. Initial term is 4.

Original entry on oeis.org

4, 14, 1411, 3114, 142113, 13311214, 14411223, 13223124, 14322123, 23322114, 14213223, 23322114
Offset: 0

Views

Author

Keywords

Comments

After a while sequence has period 2 -> {23322114,14213223}

Examples

			To get the term after 142113, we say: one 3's, three 1's, one 2's, one 4's, so 13311214
		

Crossrefs

A138489 Say what you see in previous term, from the right, reporting total number for each digit encountered. Initial term is 5.

Original entry on oeis.org

5, 15, 1511, 3115, 152113, 13311215, 15411223, 1322311415, 1541142322, 3213243115, 1531331422, 2214313315, 1531331422, 2214313315, 1531331422, 2214313315, 1531331422, 2214313315, 1531331422, 2214313315, 1531331422
Offset: 0

Views

Author

Keywords

Comments

After a while sequence has period 2 -> {1531331422,2214313315}

Examples

			To get the term after 152113, we say: one 3's, three 1's, one 2's, one 5's, so 13311215
		

Crossrefs

Previous Showing 21-30 of 44 results. Next