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.

A234575 Triangle T(n, k) read by rows: T(n, k) = floor(n/k) + n mod k.

Original entry on oeis.org

1, 2, 1, 3, 2, 1, 4, 2, 2, 1, 5, 3, 3, 2, 1, 6, 3, 2, 3, 2, 1, 7, 4, 3, 4, 3, 2, 1, 8, 4, 4, 2, 4, 3, 2, 1, 9, 5, 3, 3, 5, 4, 3, 2, 1, 10, 5, 4, 4, 2, 5, 4, 3, 2, 1, 11, 6, 5, 5, 3, 6, 5, 4, 3, 2, 1, 12, 6, 4, 3, 4, 2, 6, 5, 4, 3, 2, 1, 13, 7, 5, 4, 5, 3, 7, 6, 5
Offset: 1

Views

Author

Alex Ratushnyak, Dec 28 2013

Keywords

Examples

			Triangle begins:
   1
   2  1
   3  2  1
   4  2  2  1
   5  3  3  2  1
   6  3  2  3  2  1
   7  4  3  4  3  2  1
   8  4  4  2  4  3  2  1
   9  5  3  3  5  4  3  2  1
  10  5  4  4  2  5  4  3  2  1
  11  6  5  5  3  6  5  4  3  2  1
  12  6  4  3  4  2  6  5  4  3  2  1
  13  7  5  4  5  3  7  6  5  4  3  2  1
  14  7  6  5  6  4  2  7  6  5  4  3  2  1
  15  8  5  6  3  5  3  8  7  6  5  4  3  2  1
		

Crossrefs

Programs

  • Haskell
    a234575 n k = a234575_tabl !! (n-1) !! (k-1)
    a234575_row n = a234575_tabl !! (n-1)
    a234575_tabl = zipWith (zipWith (+)) a048158_tabl a010766_tabl
    -- Reinhard Zumkeller, Apr 29 2015
  • Mathematica
    With[{rows=10},Table[Floor[n/k]+Mod[n,k],{n,rows},{k,n}]] (* Paolo Xausa, Sep 26 2023 *)
  • Python
    for n in range(1, 19):
      for k in range(1, n+1):
        c = n//k + n%k
        print('%2d' % c, end=' ')
      print()
    
  • Python
    def T(n, k) -> int: return n - (k - 1) * (n // k)
    for n in range(1,16): print([T(n, k) for k in range(1,n+1)]) # Peter Luschny, Jun 01 2025
    
  • Scheme
    ;; MIT/GNU Scheme
    (define (A234575bi n k) (+ (floor->exact (/ n k)) (modulo n k)))
    (define (A234575 n) (A234575bi (A002024 n) (A002260 n)))
    ;; Antti Karttunen, Dec 29 2013
    

Formula

T(n, k) = A048158(n, k) + A010766(n, k). - Reinhard Zumkeller, Apr 29 2015
G.f. of the k-th column: x^k*((Sum_{i=0..k-1} x^i) - (k-1)*x^k)/((1 - x)^2*Sum_{i=0..k-1} x^i). - Stefano Spezia, May 08 2024
T(n, k) = n - (k - 1) * floor(n/k). - Peter Luschny, Jun 01 2025