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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A244567 Triangle T(n,k) in which the n-th row lists in increasing order all values s such that n is in the trajectory of the 'Reverse and Add!' sequence starting with s; triangle T(n,k), n>=0, 1<=k<=A244569(n), read by rows.

Original entry on oeis.org

0, 1, 1, 2, 3, 1, 2, 4, 5, 3, 6, 7, 1, 2, 4, 8, 9, 5, 10, 5, 10, 11, 3, 6, 12, 13, 7, 14, 15, 1, 2, 4, 8, 16, 17, 9, 18, 19, 20, 21, 5, 10, 11, 20, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 3, 6, 12, 21, 30, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43
Offset: 0

Views

Author

Alois P. Heinz, Jun 30 2014

Keywords

Examples

			Triangle T(n,k) begins:
   0;
   1;
   1,  2;
   3;
   1,  2,  4;
   5;
   3,  6;
   7;
   1,  2,  4,  8;
   9;
   5, 10;
   5, 10, 11;
   3,  6, 12;
  13;
   7, 14;
  15;
   1,  2,  4,  8,  16;
  17;
		

Crossrefs

Column k=0 gives A244568.
Last elements of rows give A001477.

A244568 Smallest value s such that n is in the trajectory of the 'Reverse and Add!' sequence starting with s.

Original entry on oeis.org

0, 1, 1, 3, 1, 5, 3, 7, 1, 9, 5, 5, 3, 13, 7, 15, 1, 17, 9, 19, 20, 21, 5, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 3, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 5, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 7, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 3, 67, 68, 69
Offset: 0

Views

Author

Alois P. Heinz, Jun 30 2014

Keywords

Crossrefs

A244569 Number of values s such that n is in the trajectory of the 'Reverse and Add!' sequence starting with s.

Original entry on oeis.org

1, 1, 2, 1, 3, 1, 2, 1, 4, 1, 2, 3, 3, 1, 2, 1, 5, 1, 2, 1, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 6, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 9, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 12, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 12, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 17
Offset: 0

Views

Author

Alois P. Heinz, Jun 30 2014

Keywords

Crossrefs

A374731 a(n) = a(n-1) + rotate(a(n-1), n-2 digits right) with a(1) = 1.

Original entry on oeis.org

1, 2, 4, 8, 16, 32, 55, 110, 121, 332, 664, 1130, 2431, 4862, 7348, 12221, 24442, 46886, 133354, 266708, 1093378, 2027159, 4054318, 12459749, 37057240, 74114480, 81525928, 110341187, 220682374, 642750611, 759178117, 876937295, 1606524988, 10422590237, 20845180474, 62929698521, 84558995506
Offset: 1

Views

Author

Nicholas M. R. Frieler, Jul 17 2024

Keywords

Examples

			a(12) = a(11) + rotate(a(11), 11) = 1130 + rotate(1130, 11) = 1130 + 1301 = 2431.
		

Crossrefs

Programs

  • Mathematica
    a[1] = 1; a[n_] := a[n] = a[n - 1] + FromDigits@RotateRight[IntegerDigits[a[n - 1]], n - 2]; arr = a[#] & /@ Range[0, 100]

A374732 a(n) = a(n-1) + rotate(a(n-1), n-1 digits right) with a(1) = 1.

Original entry on oeis.org

1, 2, 4, 8, 16, 77, 154, 569, 1264, 5390, 14443, 45887, 133345, 646679, 1443145, 6587459, 12553333, 43808666, 110246752, 321271427, 594484141, 736078625, 1598652232, 3920250884, 4804642909, 9095590955, 15005150050, 65055300101, 95065465156, 149717034662
Offset: 1

Views

Author

Nicholas M. R. Frieler, Jul 17 2024

Keywords

Examples

			a(12) = a(11) + rotate(a(11), 11) = 14443 + rotate(14443, 11) = 14443 + 31444 = 45887.
		

Crossrefs

Programs

  • Mathematica
    a[1] = 1; a[n_] := a[n] = a[n - 1] + FromDigits@RotateRight[IntegerDigits[a[n - 1]], n - 1]; arr = a[#] & /@ Range[1, 100]

A374733 a(n) = a(n-1) + rotate(a(n-1), n-2 digits left) with a(1) = 1.

Original entry on oeis.org

1, 2, 4, 8, 16, 32, 55, 110, 211, 332, 664, 1310, 1441, 2882, 11704, 52874, 105748, 586805, 1145485, 5996630, 9056596, 15962255, 41478217, 58892999, 154782298, 452937080, 1257466450, 7707592196, 9675299788, 18572052785, 46423909990, 145470333899, 484461788602
Offset: 1

Views

Author

Nicholas M. R. Frieler, Jul 17 2024

Keywords

Examples

			a(13) = a(12) + rotate_left(a(12), 11) = 1310 + rotate_left(1310, 11) = 1310 + 0131 = 1441.
		

Crossrefs

Programs

  • Mathematica
    a[1] = 1; a[n_] := a[n] = a[n - 1] + FromDigits@RotateLeft[IntegerDigits[a[n - 1]], n - 2]; arr = a[#] & /@ Range[1, 100]

A244058 n-th term of the 'Reverse and Add!' sequence starting with n.

Original entry on oeis.org

1, 4, 12, 77, 44, 363, 484, 4444, 79497, 14003, 88088, 175857, 1596595, 1716517, 17794887, 13528163, 176599676, 839546037, 1317544822, 853595347, 8836886388, 13236127322, 13297007933, 668823329856, 175304440267, 909153350908, 9317488848228, 8813200023188
Offset: 1

Views

Author

Alois P. Heinz, Jun 18 2014

Keywords

Comments

a(n) is a palindrome for n in {1, 2, 4, 5, 6, 7, 8, 9, 11, 21, 28, 30}.

Crossrefs

Main diagonal of A243238.

Programs

  • Maple
    b:= proc(n, j) option remember; `if`(j=1, n, (h-> h+ (s->
          parse(cat(s[-i]$i=1..length(s))))(""||h))(b(n, j-1)))
        end:
    a:= n-> b(n$2):
    seq(a(n), n=1..40);
  • Mathematica
    Table[Nest[#+IntegerReverse[#]&,n,n-1],{n,30}] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 07 2021 *)

A285741 a(0) = 1; a(2*n) = a(n), a(2*n+1) = a(n) + R(a(n)), where R() is the digit reversal.

Original entry on oeis.org

1, 2, 2, 4, 2, 4, 4, 8, 2, 4, 4, 8, 4, 8, 8, 16, 2, 4, 4, 8, 4, 8, 8, 16, 4, 8, 8, 16, 8, 16, 16, 77, 2, 4, 4, 8, 4, 8, 8, 16, 4, 8, 8, 16, 8, 16, 16, 77, 4, 8, 8, 16, 8, 16, 16, 77, 8, 16, 16, 77, 16, 77, 77, 154, 2, 4, 4, 8, 4, 8, 8, 16, 4, 8, 8, 16, 8, 16, 16, 77, 4, 8, 8, 16, 8, 16, 16, 77, 8, 16, 16
Offset: 0

Views

Author

Ilya Gutkovskiy, Apr 25 2017

Keywords

Examples

			a(0) = 1;
a(1) = a(2*0+1) = a(0) + R(a(0)) = 1 + 1 = 2;
a(2) = a(2*1) = a(1) = 2;
a(3) = a(2*1+1) = a(1) + R(a(1)) = 2 + 2 = 4;
a(4) = a(2*2) = a(2) = 2;
a(5) = a(2*2+1) = a(2) + R(a(2)) = 2 + 2 = 4, etc.
		

Crossrefs

Cf. A001127 (records), A004086, A056964.

Programs

  • Mathematica
    a[0] = 0; a[n_] := If[EvenQ[n], a[n/2], a[(n - 1)/2] + FromDigits[Reverse[IntegerDigits[a[(n - 1)/2]]]] ]; Table[a[n], {n, 0, 90}]
Previous Showing 11-18 of 18 results.