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A253561
Square array read by antidiagonals: A(row,col) = A122111(A246278(row,col)).
6
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
2,1
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.
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.]
EXAMPLE
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,
...
PROG
(Scheme) (define (A253561 n) (A122111 (A246278 n)))
CROSSREFS
Inverse: A253562.
The leftmost column: A000079. Topmost row: A253568.
Sequence in context: A035312 A056230 A285321 * A354960 A373623 A119919
KEYWORD
nonn,tabl
AUTHOR
Antti Karttunen, Jan 03 2015
STATUS
approved