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A257264
Square array A(row,col) read by antidiagonals: A(1,col) = A055938(col), and for row > 1, A(row,col) = A011371(A(row-1,col)).
7
2, 5, 1, 6, 3, 0, 9, 4, 1, 0, 12, 7, 3, 0, 0, 13, 10, 4, 1, 0, 0, 14, 10, 8, 3, 0, 0, 0, 17, 11, 8, 7, 1, 0, 0, 0, 20, 15, 8, 7, 4, 0, 0, 0, 0, 21, 18, 11, 7, 4, 3, 0, 0, 0, 0, 24, 18, 16, 8, 4, 3, 1, 0, 0, 0, 0, 27, 22, 16, 15, 7, 3, 1, 0, 0, 0, 0, 0, 28, 23, 19, 15, 11, 4, 1, 0, 0, 0, 0, 0, 0, 29, 25, 19, 16, 11, 8, 3, 0, 0, 0, 0, 0, 0, 0
OFFSET
1,1
COMMENTS
The array is read by antidiagonals: A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), etc.
Column n gives the trajectory of iterates of A011371, when starting from A055938(n), thus stepping through successive parent-nodes when starting from the n-th leaf of binary beanstalk, until finally reaching the fixed point 0, which is the root of the whole binary tree.
The hanging tails of columns (upward from the first encountered zero) converge towards A179016.
EXAMPLE
The top left corner of the array:
2, 5, 6, 9, 12, 13, 14, 17, 20, 21, 24, 27, 28, 29, 30, 33, 36, 37, 40, 43
1, 3, 4, 7, 10, 10, 11, 15, 18, 18, 22, 23, 25, 25, 26, 31, 34, 34, 38, 39
0, 1, 3, 4, 8, 8, 8, 11, 16, 16, 19, 19, 22, 22, 23, 26, 32, 32, 35, 35
0, 0, 1, 3, 7, 7, 7, 8, 15, 15, 16, 16, 19, 19, 19, 23, 31, 31, 32, 32
0, 0, 0, 1, 4, 4, 4, 7, 11, 11, 15, 15, 16, 16, 16, 19, 26, 26, 31, 31
0, 0, 0, 0, 3, 3, 3, 4, 8, 8, 11, 11, 15, 15, 15, 16, 23, 23, 26, 26
0, 0, 0, 0, 1, 1, 1, 3, 7, 7, 8, 8, 11, 11, 11, 15, 19, 19, 23, 23
0, 0, 0, 0, 0, 0, 0, 1, 4, 4, 7, 7, 8, 8, 8, 11, 16, 16, 19, 19
0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 4, 4, 7, 7, 7, 8, 15, 15, 16, 16
0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 3, 3, 4, 4, 4, 7, 11, 11, 15, 15
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 3, 3, 3, 4, 8, 8, 11, 11
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 3, 7, 7, 8, 8
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 4, 4, 7, 7
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 4, 4
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 3, 3
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1
...
PROG
(Scheme)
(define (A257264 n) (A257264bi (A002260 n) (A004736 n)))
(define (A257264bi row col) (if (= 1 row) (A055938 col) (A011371 (A257264bi (- row 1) col))))
CROSSREFS
Row 1: A055938, Row 2: A257507.
Sequence in context: A046527 A378764 A008343 * A093952 A308882 A079614
KEYWORD
nonn,tabl
AUTHOR
Antti Karttunen, May 03 2015
STATUS
approved