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 1-2 of 2 results.

A339094 Number of (unordered) ways of making change for n US Dollars using the current US denominations of $1, $2, $5, $10, $20, $50 and $100 bills.

Original entry on oeis.org

1, 1, 2, 2, 3, 4, 5, 6, 7, 8, 11, 12, 15, 16, 19, 22, 25, 28, 31, 34, 41, 44, 51, 54, 61, 68, 75, 82, 89, 96, 109, 116, 129, 136, 149, 162, 175, 188, 201, 214, 236, 249, 271, 284, 306, 328, 350, 372, 394, 416, 451, 473, 508, 530, 565, 600, 635, 670, 705, 740, 793, 828, 881, 916
Offset: 0

Views

Author

Robert G. Wilson v, Nov 25 2020

Keywords

Comments

Not the same as A001313. First difference appears at A001313(100) being 4562, whereas a(100) is 4563; obviously one more than A001313(100).
Not the same as A057537.
Number of partitions of n into parts 1, 2, 5, 10, 20, 50 and 100.

Examples

			a(5) is 4 because 1+1+1+1+1 = 2+1+1+1 = 2+2+1 = 5.
		

Crossrefs

Programs

  • Mathematica
    f[n_] := Length@ IntegerPartitions[n, All, {1, 2, 5, 10, 20, 50, 100}]; Array[f, 75, 0] (* or *)
    CoefficientList[ Series[1/((1 - x) (1 - x^2) (1 - x^5) (1 - x^10) (1 - x^20) (1 - x^50) (1 - x^100)), {x, 0, 75}], x] (* or *)
    Table[ Length@ FrobeniusSolve[{1, 2, 5, 10, 20, 50, 100}, n], {n, 0, 75}] (* much slower *)
  • PARI
    coins(v[..])=my(x='x); prod(i=1, #v, 1/(1-x^v[i]))
    Vec(coins(1, 2, 5, 10, 20, 50, 100)+O(x^99)) \\ Charles R Greathouse IV, Jan 24 2022

Formula

G.f.: 1/((1-x)*(1-x^2)*(1-x^5)*(1-x^10)*(1-x^20)*(1-x^50)*(1-x^100)).

A358206 Number of ways of making change for n cents using coins of 1, 2, 4, 10 and 20 cents.

Original entry on oeis.org

1, 1, 2, 2, 4, 4, 6, 6, 9, 9, 13, 13, 18, 18, 24, 24, 31, 31, 39, 39, 50, 50, 62, 62, 77, 77, 93, 93, 112, 112, 134, 134, 159, 159, 187, 187, 218, 218, 252, 252, 292, 292, 335, 335, 384, 384, 436, 436, 494, 494, 558, 558, 628, 628, 704, 704, 786, 786, 874, 874, 972, 972
Offset: 0

Views

Author

Daniel Checa, Nov 03 2022

Keywords

Comments

Number of ways of making change for 50n Colombian pesos using coins of 50, 100, 200, 500 and 1000 pesos.
Number of partitions of n into parts 1,2,4,10 and 20.

Examples

			a(5)=4 counts the ways of making change for 5 cents, these are (1,1,1,1,1), (1,1,1,2), (1,2,2), (1,4).
		

Crossrefs

Programs

  • Mathematica
    A[x_]:=1/((1 - x) (1 - x^2) (1 - x^4) (1 - x^10) (1 - x^20));
    a[n_]:=SeriesCoefficient[A[x],{x,0,n}]

Formula

G.f.: 1/((1 - x) (1 - x^2) (1 - x^4) (1 - x^10) (1 - x^20)).
a(n) = A000064(floor(n/2)).
a(n) ~ n^4/38400.
Showing 1-2 of 2 results.