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.

A247358 Triangle read by rows: n-th row contains powers b^e with b + e = n + 1 in natural order.

Original entry on oeis.org

1, 1, 2, 1, 3, 4, 1, 4, 8, 9, 1, 5, 16, 16, 27, 1, 6, 25, 32, 64, 81, 1, 7, 36, 64, 125, 243, 256, 1, 8, 49, 128, 216, 625, 729, 1024, 1, 9, 64, 256, 343, 1296, 2187, 3125, 4096, 1, 10, 81, 512, 512, 2401, 6561, 7776, 15625, 16384, 1, 11, 100, 729, 1024, 4096, 16807, 19683, 46656, 65536, 78125
Offset: 1

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Author

Reinhard Zumkeller, Sep 14 2014

Keywords

Comments

Sorted rows of triangle A051129.

Examples

			.  1  |  1                            |  1^1
.  2  |  1 2                          |  1^2 2^1
.  3  |  1 3  4                       |  1^3 3^1 2^2
.  4  |  1 4  8   9                   |  1^4 4^1 2^3 3^2
.  5  |  1 5 16  16  27               |  1^5 5^1 2^4 4^2 3^3
.  6  |  1 6 25  32  64  81           |  1^6 6^1 5^2 2^5 4^3 3^4
.  7  |  1 7 36  64 125 243 256       |  1^7 7^1 6^2 2^6 5^3 3^5 4^4
.  8  |  1 8 49 128 216 625 729 1024  |  1^8 8^1 7^2 2^7 6^3 5^4 3^6 4^5 .
		

Crossrefs

Cf. A051129, A003101 (row sums), A247363 (central terms), A003320 (row maxima).

Programs

  • Haskell
    import Data.List (sort)
    a247358 n k = a247358_tabl !! (n-1) !! (k-1)
    a247358_row n = a247358_tabl !! (n-1)
    a247358_tabl = map sort a051129_tabl
    
  • Mathematica
    Table[Table[k^(n-k+1), {k, 1, n}] // Sort, {n, 1, 11}] // Flatten (* Jean-François Alcover, Nov 18 2019 *)
  • PARI
    row(n) = vecsort(vector(n, k, k^(n-k+1))); \\ Michel Marcus, Jan 24 2022
  • Python
    from itertools import chain
    A247358_list = list(chain.from_iterable(sorted((b+1)**(n-b) for b in range(n)) for n in range(1,8))) # Chai Wah Wu, Sep 14 2014