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 1-4 of 4 results.

A164820 Numbers n such that n-th digit (after decimal point) of e and of Euler-Mascheroni constant gamma are the same.

Original entry on oeis.org

4, 30, 33, 34, 48, 49, 52, 59, 60, 66, 96, 113, 115, 134, 146, 155, 163, 169, 175, 180, 193, 196, 200, 206, 211, 235, 251, 274, 288, 300, 302, 304, 330, 336, 338, 350, 354, 358, 368, 373, 381, 399, 412, 419, 430, 436, 438, 440, 491, 506, 536, 542, 552, 579
Offset: 1

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Author

Keywords

Examples

			e = 2.7182818284..., gamma = 0.5772156649...; fourth digit of e and fourth digit of gamma are both 2, hence 4 is in the sequence.
		

Crossrefs

Programs

  • Magma
    m:=600; e:=Exp(One(RealField(m+1))); se:=IntegerToString(Round(10^m*(e-2))); g:=EulerGamma(RealField(m)); sg:=IntegerToString(Round(10^m*g)); [ a: a in [1..m] | se[a] eq sg[a] ]; // Klaus Brockhaus, Sep 03 2009
  • Maple
    P:=proc(i) local a,b,c,d,n; a:=convert(evalf(gamma,1000),string); b:=convert(evalf(exp(1)-2,1000),string); for n from 2 by 1 to i do if substring(a,n)=substring(b,n) then print(n-1); fi; od; end: P(900);
  • Mathematica
    With[{nn=600},Position[Thread[{Rest[RealDigits[E,10,nn+1][[1]]], RealDigits[ EulerGamma,10,nn][[1]]}],{x_,x_}]]//Flatten (* Harvey P. Dale, Oct 08 2017 *)

Extensions

Edited and listed terms verified by Klaus Brockhaus, Sep 03 2009

A254226 Numbers n such that the n-th decimal digit of e = 1 + the n-th decimal digit of Pi.

Original entry on oeis.org

25, 28, 31, 35, 40, 61, 73, 107, 114, 130, 135, 138, 148, 151, 152, 170, 188, 192, 195, 202, 209, 218, 222, 231, 234, 238, 263, 265, 290, 297, 315, 378, 423, 432, 436, 444, 448, 457, 470, 481, 485, 489, 490, 526, 537, 546
Offset: 1

Views

Author

Carmine Suriano, Jan 27 2015

Keywords

Examples

			31 is in the sequence since the 31st decimal digit of e is 6 and the 31st decimal digit of Pi is 5.
		

Crossrefs

Programs

  • Mathematica
    nn = 550; rdpi = RealDigits[Pi, 10, nn][[1]]; rde = RealDigits[E, 10, nn][[1]]; Select[ Range[2, nn], 1 + rdpi[[#]] == rde[[#]] &] - 1 (* Robert G. Wilson v, Feb 08 2015 *)

A164819 Numbers n such that n-th digit (after decimal point) of Pi and of Euler-Mascheroni constant gamma are the same.

Original entry on oeis.org

7, 32, 33, 40, 42, 43, 67, 72, 126, 133, 135, 137, 140, 158, 166, 169, 170, 182, 186, 191, 199, 204, 245, 246, 248, 266, 274, 284, 297, 313, 321, 329, 330, 344, 352, 372, 382, 389, 407, 419, 429, 435, 442, 458, 463, 487, 492, 495, 501, 505, 506, 551, 555, 570
Offset: 1

Views

Author

Keywords

Examples

			Pi = 3.1415926535..., gamma = 0.5772156649...; seventh digit of Pi and seventh digit of gamma are both 6, hence 7 is in the sequence.
		

Crossrefs

Programs

  • Magma
    m:=600; p:=Pi(RealField(m+1)); sp:=IntegerToString(Round(10^m*(p-3))); g:=EulerGamma(RealField(m)); sg:=IntegerToString(Round(10^m*g)); [ a: a in [1..m] | sp[a] eq sg[a] ]; // Klaus Brockhaus, Sep 03 2009
  • Maple
    P:=proc(i) local a,b,n; a:=convert(evalf(gamma,1000),string); b:=convert(evalf(Pi-3,1000),string); for n from 2 by 1 to i do if substring(a,n)=substring(b,n) then print(n-1); fi; od; end: P(900);

Formula

Presumably a(n) ~ 10n. - Charles R Greathouse IV, Sep 18 2012

Extensions

Edited and listed terms verified by Klaus Brockhaus, Sep 03 2009

A254227 Numbers such that the n-th decimal digit of Pi is one larger than the n-th decimal digit of e.

Original entry on oeis.org

5, 6, 10, 19, 26, 56, 78, 82, 96, 111, 126, 127, 160, 166, 172, 174, 216, 220, 227, 240, 242, 246, 249, 250, 272, 276, 286, 299, 314, 332, 339, 346, 351, 352, 358, 362, 365, 372, 382, 396, 402, 405, 425, 430, 442, 468, 474, 486, 487, 502
Offset: 1

Views

Author

Carmine Suriano, Jan 27 2015

Keywords

Examples

			a(2) = 6 since the 6th decimal digit of Pi is 2 and the 6th decimal digit of e is 1.
		

Crossrefs

Programs

  • Mathematica
    max = 510; piDigits = RealDigits[Pi, 10, max][[1]]; eDigits = RealDigits[E, 10, max][[1]]; Select[Range[2, max], piDigits[[#]] == 1 + eDigits[[#]] &] - 1 (* Robert G. Wilson v, Feb 08 2015 *)
Showing 1-4 of 4 results.