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A286623
Square array A(n,k) = A276943(n,k)/A002110(n-1), read by descending antidiagonals A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), etc.
9
1, 3, 1, 4, 4, 1, 5, 6, 6, 1, 7, 7, 10, 8, 1, 9, 16, 11, 14, 12, 1, 10, 19, 36, 15, 22, 14, 1, 11, 21, 41, 78, 23, 26, 18, 1, 13, 22, 45, 85, 144, 27, 34, 20, 1, 15, 31, 46, 91, 155, 222, 35, 38, 24, 1, 16, 34, 71, 92, 165, 235, 324, 39, 46, 30, 1, 17, 36, 76, 155, 166, 247, 341, 438, 47, 58, 32, 1, 18, 37, 80, 162, 287, 248, 357, 457, 668, 59, 62, 38, 1
OFFSET
1,2
FORMULA
A(n,k) = A276943(n, k) / A002110(n-1).
EXAMPLE
The top left 12 X 12 corner of the array:
1, 3, 4, 5, 7, 9, 10, 11, 13, 15, 16, 17
1, 4, 6, 7, 16, 19, 21, 22, 31, 34, 36, 37
1, 6, 10, 11, 36, 41, 45, 46, 71, 76, 80, 81
1, 8, 14, 15, 78, 85, 91, 92, 155, 162, 168, 169
1, 12, 22, 23, 144, 155, 165, 166, 287, 298, 308, 309
1, 14, 26, 27, 222, 235, 247, 248, 443, 456, 468, 469
1, 18, 34, 35, 324, 341, 357, 358, 647, 664, 680, 681
1, 20, 38, 39, 438, 457, 475, 476, 875, 894, 912, 913
1, 24, 46, 47, 668, 691, 713, 714, 1335, 1358, 1380, 1381
1, 30, 58, 59, 900, 929, 957, 958, 1799, 1828, 1856, 1857
1, 32, 62, 63, 1148, 1179, 1209, 1210, 2295, 2326, 2356, 2357
1, 38, 74, 75, 1518, 1555, 1591, 1592, 3035, 3072, 3108, 3109
PROG
(Scheme)
(define (A286623 n) (A286623bi (A002260 n) (A004736 n)))
(define (A286623bi row col) (/ (A276943bi row col) (A002110 (- row 1))))
CROSSREFS
Transpose: A286625.
Row 1: A276155.
Column 1: A000012, Column 2: A008864, Column 3: A100484, Column 4: A072055, Column 5: A023523 (from its second term onward), Column 6: A286624 (= 1 + A123134), Column 11: 2*A123134, Column 13: 3*A006094.
Cf. A276616 (analogous array).
Sequence in context: A376276 A276617 A276616 * A246340 A246354 A286625
KEYWORD
nonn,tabl
AUTHOR
Antti Karttunen, Jun 28 2017
STATUS
approved