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A277820
Square array: A(r,1) = A065621(r); for c > 1, A(r,c) = A048724(A(r,c-1)), read by descending antidiagonals as A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), etc.
13
1, 3, 2, 5, 6, 7, 15, 10, 9, 4, 17, 30, 27, 12, 13, 51, 34, 45, 20, 23, 14, 85, 102, 119, 60, 57, 18, 11, 255, 170, 153, 68, 75, 54, 29, 8, 257, 510, 427, 204, 221, 90, 39, 24, 25, 771, 514, 765, 340, 359, 238, 105, 40, 43, 26, 1285, 1542, 1799, 1020, 937, 306, 187, 120, 125, 46, 31, 3855, 2570, 2313, 1028, 1275, 854, 461, 136, 135, 114, 33, 28
OFFSET
1,2
COMMENTS
For all n >= 1, A277818 (= A268389(n)+1) gives the (one-based) index of the column where n is located in this array, while A268671(n) gives the (one-based) index of the row where it is on.
This array is obtained when one selects from A277320 the columns 1, 3, 5, 15, 17, 51, ..., i.e., those with an index A001317(k).
FORMULA
A(r,1) = A065621(r); for c > 1, A(r,c) = A048724(A(r,c-1)).
A(r,c) = A048675(A277810(r,c)).
As a composition of other permutations:
a(n) = A277901(A277880(n)).
EXAMPLE
The top left corner of the array:
1, 3, 5, 15, 17, 51, 85, 255, 257, 771, 1285, 3855
2, 6, 10, 30, 34, 102, 170, 510, 514, 1542, 2570, 7710
7, 9, 27, 45, 119, 153, 427, 765, 1799, 2313, 6939, 11565
4, 12, 20, 60, 68, 204, 340, 1020, 1028, 3084, 5140, 15420
13, 23, 57, 75, 221, 359, 937, 1275, 3341, 5911, 14649, 19275
14, 18, 54, 90, 238, 306, 854, 1530, 3598, 4626, 13878, 23130
11, 29, 39, 105, 187, 461, 599, 1785, 2827, 7453, 10023, 26985
8, 24, 40, 120, 136, 408, 680, 2040, 2056, 6168, 10280, 30840
25, 43, 125, 135, 393, 667, 1965, 2295, 6425, 11051, 32125, 34695
26, 46, 114, 150, 442, 718, 1874, 2550, 6682, 11822, 29298, 38550
31, 33, 99, 165, 495, 561, 1619, 2805, 7967, 8481, 25443, 42405
28, 36, 108, 180, 476, 612, 1708, 3060, 7196, 9252, 27756, 46260
21, 63, 65, 195, 325, 975, 1105, 3315, 5397, 16191, 16705, 50115
22, 58, 78, 210, 374, 922, 1198, 3570, 5654, 14906, 20046, 53970
19, 53, 95, 225, 291, 869, 1455, 3825, 4883, 13621, 24415, 57825
16, 48, 80, 240, 272, 816, 1360, 4080, 4112, 12336, 20560, 61680
49, 83, 245, 287, 801, 1379, 4005, 4335, 12593, 21331, 62965, 73247
50, 86, 250, 270, 786, 1334, 3930, 4590, 12850, 22102, 64250, 69390
55, 89, 235, 317, 839, 1481, 3675, 4845, 14135, 22873, 60395, 80957
PROG
(Scheme)
(define (A277820 n) (A277820bi (A002260 n) (A004736 n)))
(define (A277820bi row col) (if (= 1 col) (A065621 row) (A048724 (A277820bi row (- col 1)))))
CROSSREFS
Inverse permutation: A277821.
Transpose: A277819.
Row 1: A001317.
Column 1: A065621, column 2: A277823, column 3: A277825.
Other related tables or permutations: A277880, A277901.
Sequence in context: A257793 A376890 A302717 * A277680 A303764 A079973
KEYWORD
nonn,tabl,base
AUTHOR
Antti Karttunen, Nov 01 2016
STATUS
approved