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.

A226486 First available increasing palindromes (A002113) found in the decimal expansion of Pi-3 (A000796).

Original entry on oeis.org

1, 4, 5, 9, 535, 979, 46264, 59195, 73637, 77477, 99999, 467764, 8683868, 23911932, 398989893, 559555955, 769646967, 972464279, 992868299, 21348884312, 49612121694, 450197791054, 9475082805749
Offset: 1

Views

Author

Patrick De Geest and Robert G. Wilson v, Jun 09 2013

Keywords

Crossrefs

Cf. A000796, A068046, A226487.

Programs

  • Mathematica
    pi = RealDigits[Pi-3, 10, 2500000][[1]]; palQ[n_] := n == Reverse[n]; mx = 0; k = 1; While[k < 1000, j = 1; While[j <= k, If[ palQ[ Take[ pi, {j, k}]], p = FromDigits[ Take[ pi, {j, k}]]; If[p > mx, mx = p; Print[p]; pi = Drop[pi, k]; k = 0; Break[]]]; j++]; k++]

A068047 Starting position of the n-th nontrivial palindrome in decimal expansion of Pi.

Original entry on oeis.org

2, 9, 13, 16, 20, 21, 25, 26, 35, 43, 44, 45, 58, 60, 79, 80, 95, 106, 112, 113, 118, 126, 131, 132, 136, 142, 151, 154, 154, 155, 175, 178, 178, 179, 182, 183, 186, 195, 202, 205, 211, 212, 216, 218, 231, 247, 248, 258, 272, 277
Offset: 1

Views

Author

Reinhard Zumkeller, Feb 11 2002

Keywords

Comments

A000796(a(n)) is the first digit of the n-th nontrivial palindrome.

Crossrefs

Cf. A068046, A000796.

A068048 Length of the n-th nontrivial palindrome in decimal expansion of Pi.

Original entry on oeis.org

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

Views

Author

Reinhard Zumkeller, Feb 11 2002

Keywords

Crossrefs

Cf. A068046.

A226536 Palindromes of length greater than 1 in decimal expansion of e (A001113).

Original entry on oeis.org

828, 18281, 818, 28182, 8281828, 828, 353, 747, 66, 2662, 77, 757, 99, 999, 99, 959, 595, 66, 9669, 696, 676, 77, 2772, 66, 303, 353, 535, 525, 66, 66, 919, 39193, 0, 30, 99, 181, 66, 0, 33, 595, 323, 232, 434, 94349, 323, 33, 88, 525, 101, 11, 383, 70, 99, 88, 4884, 44, 606, 66, 808, 22
Offset: 1

Views

Author

Reinhard Zumkeller and Robert G. Wilson v, Jun 09 2013

Keywords

Comments

Begin with the left (most significant) k digits and sequentially remove the first j leading digits until a palindrome is found; continue.
a(33) is actually '00', a(34) is actually '030' (which should be obvious), a(38) is actually '00'.
If e is normal number then all multidigit palindromes should appear.

Examples

			e = 2.7182818284590452353602874713526624977572470936999595749669676...
a(1) = 828, as the first nontrivial palindrome in E is '828', which appears in the digits 4 through 6.
a(2) = 18281, as the second nontrivial palindrome in E is '18281', which appears in the digits 3 through 7.
Please note that a(1) runs from digits 4-6 whereas a(2) runs from 3-7. This is why a(1) appears before a(2).

Links

Crossrefs

Cf. A001113, A002113, A068046, A099052.

Programs

  • Mathematica
    e = RealDigits[E, 10, 250][[1]]; palQ[n_] := n == Reverse[n]; k = 2; lst = {}; While[k < 251, While[j < k, If[ palQ[ Take[e, {j, k}]], p = FromDigits[Take[e, {j, k}]]; AppendTo[lst, p]; Print[p]]; j++]; k++; j = 1]

A242946 Palindromes of length greater than 1 in decimal expansion of Blazys's constant (A233588).

Original entry on oeis.org

5665, 66, 383, 171, 88, 888, 88, 44, 444, 44, 33, 22, 575, 282, 828, 464, 969, 33, 525, 66, 99, 989, 40, 0, 22, 88, 5665, 66, 3003, 0, 383, 8338, 33, 62526, 252, 55, 808, 585, 33, 99, 545, 77, 44, 0, 11, 44, 282, 696, 99, 44, 444, 44, 646, 919, 212, 0, 99, 44, 444, 44, 353, 535, 595, 252, 22
Offset: 1

Views

Author

Robert G. Wilson v, May 27 2014

Keywords

Comments

Begin with the left (most significant) k digits and sequentially remove the first j leading digits until a palindrome is found; continue.
a(23) is actually 040 (which should be obvious), a(24) is 00, a(30) is 00, a(44) is 00, a(56) is 00, etc.
If the Blazys's constant is a normal number then all palindromes should eventually appear.

Examples

			Blazys's constant is 2.566543832171388844467529106332285751782972828702314645...

Links

Crossrefs

Cf. A002113, A068046, A226536, A233588.

Programs

  • Mathematica
    bc = RealDigits[ Fold[(#2 + #2/#1) &, 1, Reverse@ Prime@ Range@ 1000], 10, 1000][[1]]; palQ[n_] := n == Reverse[n]; k = 1; lst = {}; While[j = k + 1; k < 600, While[j < 600 - k, If[ palQ[ Take[ bc, {k, j}]], p = FromDigits[ Take[ bc, {k, j}]]; AppendTo[lst, p]; Print[p]]; j++]; k++]; lst
Showing 1-5 of 5 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.