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A255543 Unlucky array: Row n consists of unlucky numbers removed at the stage n of Lucky sieve. 20
2, 4, 5, 6, 11, 19, 8, 17, 39, 27, 10, 23, 61, 57, 45, 12, 29, 81, 91, 97, 55, 14, 35, 103, 121, 147, 117, 85, 16, 41, 123, 153, 199, 181, 177, 109, 18, 47, 145, 183, 253, 243, 277, 225, 139, 20, 53, 165, 217, 301, 315, 369, 345, 295, 157, 22, 59, 187, 247, 351, 379, 471, 465, 447, 325, 175, 24, 65, 207, 279, 403, 441, 567, 589, 603, 493, 381, 213 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The array A(row,col) is read by antidiagonals A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), ...

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..5886; the first 108 antidiagonals of the array, flattened

EXAMPLE

Top left corner of the square array:

    2,   4,   6,   8,  10,  12,   14,   16,   18,   20,  22,    24,   26,   28,   30

    5,  11,  17,  23,  29,  35,   41,   47,   53,   59,  65,    71,   77,   83,   89

   19,  39,  61,  81, 103, 123,  145,  165,  187,  207, 229,   249,  271,  291,  313

   27,  57,  91, 121, 153, 183,  217,  247,  279,  309, 343,   373,  405,  435,  469

   45,  97, 147, 199, 253, 301,  351,  403,  453,  507, 555,   609,  661,  709,  763

   55, 117, 181, 243, 315, 379,  441,  505,  571,  633, 697,   759,  825,  889,  951

   85, 177, 277, 369, 471, 567,  663,  757,  853,  949, 1045, 1141, 1239, 1333, 1431

  109, 225, 345, 465, 589, 705,  829,  945, 1063, 1185, 1305, 1423, 1549, 1669, 1789

  139, 295, 447, 603, 765, 913, 1075, 1227, 1377, 1537, 1689, 1843, 1999, 2155, 2313

  157, 325, 493, 667, 835, 999, 1177, 1347, 1513, 1687, 1861, 2029, 2205, 2367, 2535

...

MATHEMATICA

rows = cols = 12; L = 2 Range[0, 2000] + 1; A = Join[{2 Range[cols]}, Reap[For[n = 2, n <= rows, r = L[[n++]]; L0 = L; L = ReplacePart[L, Table[r i -> Nothing, {i, 1, Length[L]/r}]]; Sow[Complement[L0, L][[1 ;; cols]]]]][[2, 1]]]; Table[A[[n - k + 1, k]], {n, 1, Min[rows, cols]}, {k, n, 1, -1}] // Flatten (* Jean-Fran├žois Alcover, Mar 15 2016 *)

PROG

(Scheme)

(define (A255543 n) (A255543bi (A002260 n) (A004736 n)))

(define (A255543bi row col) ((rowfun_n_for_A255543 row) col))

;; Uses the memoizing definec-macro:

(definec (rowfun_n_for_A255543 n) (if (= 1 n) (lambda (n) (+ n n)) (let* ((rowfun_for_remaining (rowfun_n_for_A000959sieve (- n 1))) (eka (A000959 n))) (compose rowfun_for_remaining (lambda (n) (* eka n))))))

(definec (rowfun_n_for_A000959sieve n) (if (= 1 n) A005408shifted (let* ((prevrowfun (rowfun_n_for_A000959sieve (- n 1))) (everynth (prevrowfun n))) (compose-funs prevrowfun (nonzero-pos 1 1 (lambda (i) (modulo i everynth)))))))

(definec (A000959 n) ((rowfun_n_for_A000959sieve n) n))

(define (A005408shifted n) (- (* 2 n) 1))

CROSSREFS

Permutation of A050505.

Row 1: A005843 (after zero), Row 2: A016969.

Column 1: A219178.

Main diagonal: A255549. The first subdiagonal: A255550 (apart from the initial term).

Transpose: A255544.

This is array A255545 without its leftmost column, A000959.

Cf. also arrays A255127 and A255551.

Sequence in context: A194607 A194637 A194600 * A256458 A276001 A182109

Adjacent sequences:  A255540 A255541 A255542 * A255544 A255545 A255546

KEYWORD

nonn,tabl

AUTHOR

Antti Karttunen, Feb 25 2015

STATUS

approved

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Last modified March 1 03:32 EST 2021. Contains 341732 sequences. (Running on oeis4.)