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A085180
Array A(x,y) giving the position of the y-th x in A007001 listed by rising antidiagonals.
4
1, 2, 3, 5, 4, 6, 14, 10, 7, 8, 42, 28, 13, 9, 11, 132, 84, 37, 19, 12, 15, 429, 264, 112, 41, 24, 16, 17, 1430, 858, 354, 126, 56, 27, 18, 20, 4862, 2860, 1155, 402, 131, 70, 33, 21, 22, 16796, 9724, 3861, 1320, 422, 174, 79, 36, 23, 25, 58786, 33592, 13156, 4433
OFFSET
1,2
COMMENTS
Read by upwards antidiagonals as A(1,1), A(2,1), A(1,2), A(3,1), A(2,2), A(1,3), etc.
EXAMPLE
In A007001 each n occurs for the first time at position Cat(n), thus A(x,1) (the first row) is A000108.
CROSSREFS
Variant: A085178.
Inverse permutation: A085181.
First row: A000108, second row: A068875 apart from initial terms, first column: A085197, central diagonal: A001453.
Sequence in context: A352943 A143514 A374801 * A360209 A114750 A234923
KEYWORD
nonn,tabl
AUTHOR
Antti Karttunen, Jun 18 2003
STATUS
approved