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 A255551 Lucky / Unlucky array, shifted version, read by antidiagonals A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), ... 19
 2, 4, 3, 6, 5, 7, 8, 11, 19, 9, 10, 17, 39, 27, 13, 12, 23, 61, 57, 45, 15, 14, 29, 81, 91, 97, 55, 21, 16, 35, 103, 121, 147, 117, 85, 25, 18, 41, 123, 153, 199, 181, 177, 109, 31, 20, 47, 145, 183, 253, 243, 277, 225, 139, 33, 22, 53, 165, 217, 301, 315, 369, 345, 295, 157, 37, 24, 59, 187, 247, 351, 379, 471, 465, 447, 325, 175, 43 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS Note how in comparison to A255545, the even numbers on the first row have been shifted one step left, "pushing" term 1 out of the array proper. This was done to obtain a better alignment with arrays like A083221 and A255127 associated with other sieves, from which one may then induce permutations like A255553 by cross-referencing. The starting offset of the sequence giving the terms in square array is 2. However, we can tacitly assume that a(1) = 1 when the sequence is used one-dimensionally as a permutation of natural numbers. LINKS FORMULA For row = 1, A(row,col) = 2*col; For row > 1 and col = 1, A(row,col) = A000959(row); otherwise, A(row,col) = A255543(row,col-1). EXAMPLE The top left corner of the array:    2,   4,   6,   8,  10,  12,  14,   16,   18,   20,   22,   24,   26,   28,   30    3,   5,  11,  17,  23,  29,  35,   41,   47,   53,   59,   65,   71,   77,   83    7,  19,  39,  61,  81, 103, 123,  145,  165,  187,  207,  229,  249,  271,  291    9,  27,  57,  91, 121, 153, 183,  217,  247,  279,  309,  343,  373,  405,  435   13,  45,  97, 147, 199, 253, 301,  351,  403,  453,  507,  555,  609,  661,  709   15,  55, 117, 181, 243, 315, 379,  441,  505,  571,  633,  697,  759,  825,  889   21,  85, 177, 277, 369, 471, 567,  663,  757,  853,  949, 1045, 1141, 1239, 1333   25, 109, 225, 345, 465, 589, 705,  829,  945, 1063, 1185, 1305, 1423, 1549, 1669   31, 139, 295, 447, 603, 765, 913, 1075, 1227, 1377, 1537, 1689, 1843, 1999, 2155   33, 157, 325, 493, 667, 835, 999, 1177, 1347, 1513, 1687, 1861, 2029, 2205, 2367 ... PROG (Scheme) (define (A255551 n) (if (<= n 1) n (A255551bi (A002260 (- n 1)) (A004736 (- n 1))))) (define (A255551bi row col) (cond ((= 1 row) (+ col col)) ((= 1 col) (A000959 row)) (else (A255543bi row (- col 1))))) ;; Other code as in A255543. CROSSREFS Inverse: A255552. Variant of array A255545. (See also A255543). Row 1: A005843 (even numbers). Column 1: 2 followed by A000959(2..) (Lucky numbers from their second term onward). Main diagonal: A255550. Similar arrays: A083221, A255127. Associated permutations: A255553, A255554. Sequence in context: A278512 A278511 A255552 * A332072 A330340 A328696 Adjacent sequences:  A255548 A255549 A255550 * A255552 A255553 A255554 KEYWORD nonn,tabl AUTHOR Antti Karttunen, Feb 26 2015 STATUS approved

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Last modified July 29 02:36 EDT 2021. Contains 346340 sequences. (Running on oeis4.)