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.

Previous Showing 11-18 of 18 results.

A161406 Write the Spanish name for n (ignoring spaces) and add numerical values of letters using a=1, b=2, ..., ñ=15, ..., y=26, z=27, n >= 0.

Original entry on oeis.org

43, 52, 40, 65, 82, 45, 54, 60, 43, 69, 45, 38, 28, 53, 68, 71, 84, 90, 73, 99, 77, 133, 121, 146, 163, 126, 135, 141, 124, 150, 90, 168, 156, 181, 198, 161, 170, 176, 159, 185, 86, 164, 152, 177, 194, 157, 166, 172, 155, 181, 92, 170, 158, 183, 200, 163, 172, 178, 161
Offset: 0

Views

Author

Claudio Meller, Jun 09 2009

Keywords

Comments

Spanish has one more letter than English: ñ is the 15th letter.

Examples

			From _Omar E. Pol_, May 10 2021: (Start)
----------------------------------------------------
   n      Name     Calculation                  a(n)
----------------------------------------------------
   0      Cero      3 +  5 + 19 + 16           = 43
   1      Uno      22 + 14 + 16                = 52
   2      Dos       4 + 16 + 20                = 40
   3      Tres     21 + 19 +  5 + 20           = 65
   4      Cuatro    3 + 22 +  1 + 21 + 19 + 16 = 82
   5      Cinco     3 +  9 + 14 +  3 + 16      = 45
   6      Seis     20 +  5 +  9 + 20           = 54
   7      Siete    20 +  9 +  5 + 21 +  5      = 60
   8      Ocho     16 +  3 +  8 + 16           = 43
   9      Nueve    14 + 22 +  5 + 23 +  5      = 69
  10      Diez      4 +  9 +  5 + 27           = 45
  11      Once     16 + 14 +  3 +  5           = 38
  12      Doce      4 + 16 +  3 +  5           = 28
... (End)

Crossrefs

For analogs in other languages see A073327 (U.S. English), A169639 (French), A119945 (German).

Extensions

Name edited and offset corrected by Omar E. Pol, Jun 10 2021

A362065 Write the English name of a(n); sum the ranks of its letters in the alphabet; divide the sum by a(n); the result is an integer.

Original entry on oeis.org

1, 2, 4, 16, 134
Offset: 1

Views

Author

Eric Angelini and Mensanator, Apr 07 2023

Keywords

Comments

Is a(5) = 134 the last such term?
Indices of zeros in A226911; and conjectured finite, full based on an observation there. - Michael S. Branicky, Apr 07 2023
If a(6) exists, it is > 10^7. - Robert G. Wilson v, Apr 22 2023
There are no more terms because for any number k > 10^6, the sum of the ranks of the letters in the English name of k will be far less than k. - Erich Friedman, Nov 13 2024

Examples

			a(1) = 1 = ONE and O+N+E = 34 and 34/1 = 34;
a(2) = 2 = TWO and T+W+O = 58 and 58/2 = 29;
a(3) = 4 = FOUR and F+O+U+R = 60 and 60/4 = 15;
a(4) = 16 = SIXTEEN and S+I+X+T+E+E+N = 96 and 96/16 = 6; etc.

Crossrefs

Cf. A092320, A126259, A073327, A226911.

Programs

  • Mathematica
    Position[Array[Mod[Total@ Flatten[ToCharacterCode[#] - 96 & /@ Characters@ StringDelete[IntegerName[#], Except@ LetterCharacter]], #] &, 10^4] , 0][[All, 1]] (* Michael De Vlieger, Apr 07 2023 *)

A345240 a(1) = 1; thereafter a(n) = A161406(a(n-1)).

Original entry on oeis.org

1, 52, 158, 229, 278, 284, 304, 235, 289, 291, 300, 153, 251, 298, 291, 300, 153, 251, 298, 291, 300, 153, 251, 298, 291, 300, 153, 251, 298, 291, 300, 153, 251, 298, 291, 300, 153, 251, 298, 291, 300, 153, 251, 298, 291, 300, 153, 251, 298, 291, 300, 153, 251, 298
Offset: 1

Views

Author

Omar E. Pol and N. J. A. Sloane, Jun 11 2021

Keywords

Comments

A Spanish analog of A345126 (British English) and A345157 (US English).
Starting from n = 10 the sequence becomes periodic with period 5: repeat [291, 300, 153, 251, 298].

Links

Crossrefs

Cf. A073327, A161406, A169639, A344013, A345126, A345157.

Programs

  • Mathematica
    a[1]=1;a[n_]:=a[n]=Total[If[#=="ñ",15,If[(s=LetterNumber@#)>14,s+1,s]]&/@Characters@StringDelete[IntegerName[a[n-1],"Spanish"],{" ","-"}]];Array[a,100] (* Giorgos Kalogeropoulos, Jun 11 2021 *)
PadRight[{1,52,158,229,278,284,304,235,289},120,{300,153,251,298,291}] (* Harvey P. Dale, Sep 26 2024 *)

A119482 Numbers that are diminished by taking its sum of letters (writing out its English name and adding the letters using a=1, b=2, c=3, ...).

Original entry on oeis.org

80, 90, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 215, 218, 219, 240, 250, 251, 255, 256, 258, 259, 260, 270, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307
Offset: 1

Views

Author

Tanya Khovanova, Jul 26 2006

Keywords

Comments

Note, since 202 a term, this is American English (e.g. 'two hundred two', not 'two hundred and two'). - Alvin Hoover Belt, Jan 16 2016
Numbers that satisfy A073327(n) < n. - Michel Marcus, Jan 17 2016

Examples

			EIGHTY = 5+9+7+8+20+25 = 74, so 80 is in the sequence.

Links

Crossrefs

Cf. A073327.

Programs

  • Mathematica
    f[n_] := Block[{w, g, d = FromDigits /@ If[IntegerLength@ n > 3, Reverse@ TakeDrop[IntegerDigits@ n, -3], {IntegerDigits@ n}], r = <| 2 -> "hundred", 3 -> "thousand" |>, s = <| 10 -> "ten", 20 -> "twenty", 30 -> "thirty", 40 -> "forty", 50 -> "fifty", 60 -> "sixty", 70 -> "seventy", 80 -> "eighty", 90 -> "ninety" |>, t = <| 10 -> "ten", 11 -> "eleven", 12 -> "twelve", 13 -> "thirteen", 14 -> "fourteen", 15 -> "fifteen", 16 -> "sixteen", 17 -> "seventeen", 18 -> "eighteen", 19 -> "nineteen"|>, u = <| 0 -> "", 1 -> "one", 2 -> "two", 3 -> "three", 4 -> "four", 5 -> "five", 6 -> "six", 7 -> "seven", 8 -> "eight", 9 -> "nine" |>}, g[x_] := StringJoin[If[# == 0, "", Lookup[u, #] <> " " <> Lookup[r, 2]] &@ Floor[#/10^2] &@ x, " ", Which[0 <= # < 10, Lookup[u, #], 10 <= # < 20, Lookup[t, #], True, Lookup[s, 10 First@ #] <> " " <> Lookup[u, Last@ #] &@ IntegerDigits@ #] &@ (# - 10^2 Floor[#/10^2]) &@ x]; w = If[Length@ d == 2, g@ First@ d <> " " <> Lookup[r, 3] <> " " <> g@ Last@ d, g@ First@ d]; StringReplace[StringTrim@ w, "  " -> " "]]; Select[Range@ 300, Total[ToCharacterCode[StringReplace[f@ #, " " -> ""]] - 96] < # &] (* Michael De Vlieger, Jan 18 2016 *)
  • PARI
    for (n=1, 1000, if (A073327(n) < n, print1(n, ", "))) \\ using PARI scripts from A052360 and A073327; Michel Marcus, Jan 18 2016

Extensions

More terms from Alvin Hoover Belt, Jan 16 2016

A224343 The digits of Pi, spelled in English and summed with A=1, B=2, ..., Z=26.

Original entry on oeis.org

56, 34, 60, 34, 42, 42, 58, 52, 42, 56, 42, 49, 42, 65, 42, 56, 58, 56, 49, 60, 52, 58, 52, 60, 56, 56, 49, 56, 58, 65, 42, 42, 64, 58, 49, 49, 60, 34, 42, 65, 34, 52, 42, 56, 42, 42, 56, 65, 42, 34, 64, 42, 49, 58, 64, 42, 65, 60, 42, 60, 60, 42, 42, 58, 56, 64
Offset: 1

Views

Author

Kevin L. Schwartz and Christian N. K. Anderson, Apr 04 2013

Keywords

Comments

This is A073327(A000796).
To include "POINT" as a(2), insert the value 74 after the first number.

Examples

			The first digit of pi is the sum of T=20 H=8 R=18 E=5 E=5 == 56.

Links

Crossrefs

Cf. A073327, A000796, A224359.

A224359 The decimal expansion of e, spelled in English, and each digit summed where A=1, B=2, ..., Z=26.

Original entry on oeis.org

58, 65, 34, 49, 58, 49, 34, 49, 58, 49, 60, 42, 42, 64, 60, 42, 58, 56, 42, 56, 52, 64, 58, 49, 65, 60, 65, 34, 56, 42, 58, 52, 52, 58, 60, 42, 65, 65, 42, 65, 58, 60, 65, 64, 42, 56, 52, 42, 42, 42, 42, 42, 42, 65, 60, 42, 52, 52, 42, 52, 65, 52, 58, 65, 65, 58
Offset: 1

Views

Author

Kevin L. Schwartz and Christian N. K. Anderson, Apr 04 2013

Keywords

Comments

To include "POINT" as the second term, insert the value 74 as a(2).

Examples

			The first digit of e is represented as T=20 + W=23 + O=15 == 58.

Crossrefs

Cf. A073327, A001113.

Formula

a(n) = A073327(A001113(n)).

A226942 Number of iterations of A226911 until 0 is reached, for starting value n.

Original entry on oeis.org

1, 1, 2, 1, 2, 2, 2, 2, 3, 4, 3, 3, 3, 3, 3, 1, 3, 2, 5, 3, 4, 4, 2, 3, 4, 3, 5, 2, 2, 5, 5, 6, 4, 4, 2, 3, 4, 3, 5, 2, 4, 2, 4, 4, 4, 5, 3, 5, 3, 2, 4, 4, 2, 3, 3, 3, 4, 5, 4, 5, 4, 6, 6, 3, 4, 4, 3, 5, 2, 3, 2, 4, 4, 5, 2, 5, 5, 3, 5, 6, 6, 3, 4
Offset: 1

Views

Author

M. F. Hasler, Jun 23 2013

Keywords

Comments

Iterating the map A226911 was suggested in the SeqFan post by E. Angelini, cf link.

Links

Crossrefs

Cf. A073327, A073029, A119945, A072922, A075831, A152611, A052360.

Programs

  • Maple
    f:= proc(n) local S;
  uses StringTools;
  S:= Select(IsAlpha, convert(n, english));
  convert(map(`-`, convert(S, bytes), 96), `+`) mod n
end proc:
g:= proc(n) option remember;
    local v;
    v:= f(n);
    1+procname(v)
end proc:
g(0):= 0:
map(g, [$1..100]); # Robert Israel, Jun 13 2019
  • PARI
    A226942 = n -> for(c=1,9e9,(n=A226911(n))||return(c))

A344013 a(1)=1; thereafter a(n) = A169639(a(n-1)).

Original entry on oeis.org

1, 35, 125, 157, 206, 148, 197, 293, 333, 286, 302, 177, 246, 245, 236, 230, 178, 244, 275, 295, 342, 274, 326, 247, 253, 281, 285, 293, 333, 286, 302, 177, 246, 245, 236, 230, 178, 244, 275, 295, 342, 274, 326, 247, 253, 281, 285, 293, 333, 286, 302, 177, 246, 245, 236, 230, 178, 244, 275
Offset: 1

Views

Author

Simon Plouffe and N. J. A. Sloane, Jun 10 2021

Keywords

Comments

A French analog of A345126 (British English) and A345157 (US English).
Enters a cycle of length 20 starting from a(8). - Chai Wah Wu, Jun 12 2021

Examples

			1 = un -> 35 = trente-cinq -> 125 -> cent vingt cinq = 157.

Crossrefs

Cf. A073327, A169639, A345240, A345126, A345157.

Programs

  • Mathematica
    a[1]=1;a[n_]:=a[n]=Total@LetterNumber@StringDelete[IntegerName[a[n-1],"French"],{" ","-"}];Array[a,100] (* Giorgos Kalogeropoulos, Jun 11 2021 *)
  • Python
    from num2words import num2words
from unidecode import unidecode
A344013_list = [1]
for _ in range(10):
    A344013_list.append(sum(ord(s)-96 for s in unidecode(num2words(A344013_list[-1],lang='fr')) if s.isalpha())) # Chai Wah Wu, Jun 11 2021

Extensions

More terms from Chai Wah Wu, Jun 11 2021
Previous Showing 11-18 of 18 results.

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