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.

A253561 Square array read by antidiagonals: A(row,col) = A122111(A246278(row,col)).

Original entry on oeis.org

2, 3, 4, 6, 9, 8, 5, 18, 27, 16, 12, 25, 54, 81, 32, 10, 36, 125, 162, 243, 64, 24, 50, 108, 625, 486, 729, 128, 7, 72, 250, 324, 3125, 1458, 2187, 256, 15, 49, 216, 1250, 972, 15625, 4374, 6561, 512, 20, 75, 343, 648, 6250, 2916, 78125, 13122, 19683, 1024, 48, 100, 375, 2401, 1944, 31250, 8748, 390625, 39366, 59049, 2048, 14, 144, 500, 1875, 16807, 5832, 156250, 26244, 1953125, 118098, 177147, 4096
Offset: 2

Views

Author

Antti Karttunen, Jan 03 2015

Keywords

Comments

If we assume here that a(1) = 1 (but which is not explicitly included because outside of the array), then A253562 gives the inverse permutation.
The top row A253568 contains the same terms as A102750, but in different order.

Examples

			The top left corner of the array:
   2,  3,   6,   5,   12,   10,   24,    7,   15,   20,  48,   14,  96,   40,
   4,  9,  18,  25,   36,   50,   72,   49,   75,  100, 144,   98, 288,  200,
   8, 27,  54, 125,  108,  250,  216,  343,  375,  500, 432,  686, 864, 1000,
  16, 81, 162, 625,  324, 1250,  648, 2401, 1875, 2500,1296, 4802,2592, 5000,
  32,243, 486,3125,  972, 6250, 1944,16807, 9375,12500,3888,33614,7776,25000,
...
		

Crossrefs

Inverse: A253562.
The leftmost column: A000079. Topmost row: A253568.

Programs

Formula

a(n) = A122111(A246278(n)). [As a linear sequence].
Other identities.
A071178(A(row,col)) = row for all col. [All terms on row k have k as the exponent of their largest prime factor.]
A253560(A(row,col)) = A(row+1,col). [For any n >= 2, A253560(n) gives the term which is immediately below n in the same column of this array.]

A252752 Inverse permutation to sequence A246278 when it is considered as a permutation of natural numbers (with assumption that a(1) = 1).

Original entry on oeis.org

1, 2, 4, 3, 7, 5, 11, 8, 6, 12, 16, 17, 22, 23, 9, 30, 29, 38, 37, 47, 18, 57, 46, 68, 10, 80, 13, 93, 56, 107, 67, 122, 31, 138, 14, 155, 79, 173, 69, 192, 92, 212, 106, 233, 24, 255, 121, 278, 15, 302, 94, 327, 137, 353, 25, 380, 156, 408, 154, 437, 172, 467, 58, 498, 40, 530, 191, 563, 193, 597, 211, 632, 232, 668, 48, 705, 20
Offset: 1

Views

Author

Antti Karttunen, Jan 03 2015

Keywords

Crossrefs

Inverse of array A246278 considered as a permutation of natural numbers with prepended a(1) = 1.
Related permutations A122111, A156552, A246276, A253552, A253562.
Differs from A252460 for the first time at n=21, where a(21) = 18, while A252460(21) = 13.

Formula

a(1) = 1; for n>1: a(n) = 1 + A246276(n-1).
As a composition of related permutations:
a(n) = A253562(A122111(n)).
a(n) = 1 + A253552(A156552(n)).
Showing 1-2 of 2 results.