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 1-3 of 3 results.

A064692 Total number of holes in decimal expansion of the number n, assuming 4 has 1 hole.

Original entry on oeis.org

1, 0, 0, 0, 1, 0, 1, 0, 2, 1, 1, 0, 0, 0, 1, 0, 1, 0, 2, 1, 1, 0, 0, 0, 1, 0, 1, 0, 2, 1, 1, 0, 0, 0, 1, 0, 1, 0, 2, 1, 2, 1, 1, 1, 2, 1, 2, 1, 3, 2, 1, 0, 0, 0, 1, 0, 1, 0, 2, 1, 2, 1, 1, 1, 2, 1, 2, 1, 3, 2, 1, 0, 0, 0, 1, 0, 1, 0, 2, 1, 3, 2, 2, 2, 3, 2, 3, 2, 4, 3, 2, 1, 1, 1, 2, 1, 2, 1, 3, 2, 2, 1, 1, 1, 2
Offset: 0

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Author

Matthew Conroy, Oct 11 2001

Keywords

Examples

			We assume decimal digits 1,2,3,5,7 have no hole; 0,4,6,9 have one hole each; 8 has two holes. So a(148)=3.
		

Crossrefs

Programs

  • Mathematica
    Table[DigitCount[x].{0, 0, 0, 1, 0, 1, 0, 2, 1, 1}, {x, 0, 104}] (* Zak Seidov, Jul 25 2015 *)
  • Python
    def A064692(n):
        x=str(n)
        return x.count("0")+x.count("4")+x.count("6")+x.count("8")*2+x.count("9") # Indranil Ghosh, Feb 02 2017

Formula

a(A001742(n)) = 0. - Michel Marcus, Jul 25 2015

A064530 Number of holes in n-th capital letter of English alphabet.

Original entry on oeis.org

1, 2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0
Offset: 1

Views

Author

N. J. A. Sloane, Oct 07 2001

Keywords

Examples

			A has one hole, B has two, etc.
		

Crossrefs

Equals A064529 - 1. Cf. A064531, A064532, A208568.

A185374 Number of holes in n-th lower case letter of English alphabet (in printed form using standard Times New Roman font).

Original entry on oeis.org

1, 1, 0, 1, 1, 0, 2, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0
Offset: 1

Views

Author

Alex Bellos, Feb 29 2012

Keywords

Comments

The letter a has one hole, b has one hole, c has no holes, ...

Crossrefs

Showing 1-3 of 3 results.