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.

User: S. Alwin Mao

S. Alwin Mao's wiki page.

S. Alwin Mao has authored 2 sequences.

A332492 Self-locating numbers within the decimal expansion of log(2): strings k beginning at position k (first digit after decimal point is position 2).

Original entry on oeis.org

7, 23, 52, 54, 86, 303, 389, 5112, 60392, 87491, 94788, 97115, 616916, 672938066
Offset: 1

Author

S. Alwin Mao, Feb 14 2020

Keywords

Comments

a(15) > 10^9.
52 and 54 are self-locating numbers which appear consecutively in log(2) = 0.693...5254....

Examples

			For 0.693147..., if 6 appears at position 2, then 7 appears at position 7.
		

Crossrefs

Decimal expansion of log(2): A002162.
Self-locating digits of Pi: A057679, A153220.

Programs

  • Mathematica
    dlog2 = RealDigits[Log[2], 10, 1000010][[1]]; Select[Range[2, 1000000], FromDigits[Take[dlog2, {# - 1, # - 2 + IntegerLength[#]}]] == # &] (* Vaclav Kotesovec, Feb 18 2020 *)

A331015 Self-locating strings within Euler-Mascheroni Constant (gamma), strings k at position k (taking gamma offset 1).

Original entry on oeis.org

57, 16939, 767158, 5505709, 6674196, 7418985, 18873720
Offset: 1

Author

S. Alwin Mao, Feb 12 2020

Keywords

Comments

The first self-locating digits of gamma are 57, and the first digits of gamma are 57.
A near-miss '04305165' begins at position 4305165.

Examples

			57 is a term because the 57th digit is 5 and the 58th digit is 7.
		

Crossrefs

Euler-Mascheroni constant digits: A001620.
Self-locating digits of Pi: A057679, A064810 and e: A205648.

Programs

  • Mathematica
    dgamma = RealDigits[EulerGamma, 10, 1000010][[1]]; Select[Range[1000000], FromDigits[Take[dgamma, {#, # - 1 + IntegerLength[#]}]] == # &] (* Vaclav Kotesovec, Feb 18 2020 *)