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A278505 Square array constructed from Flavius sieve: Each row n (n >= 1) starts with A000960(n), followed by all numbers removed at the stage n of the sieve. 9
1, 2, 3, 4, 5, 7, 6, 11, 9, 13, 8, 17, 21, 15, 19, 10, 23, 33, 37, 25, 27, 12, 29, 45, 55, 51, 31, 39, 14, 35, 57, 75, 85, 73, 43, 49, 16, 41, 69, 97, 111, 121, 99, 61, 63, 18, 47, 81, 115, 145, 159, 151, 127, 67, 79, 20, 53, 93, 135, 171, 199, 211, 193, 163, 87, 91, 22, 59, 105, 157, 205, 243, 267, 271, 247, 187, 103, 109 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
The array A(row,col) is read by descending antidiagonals A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), ...
LINKS
FORMULA
A(row,1) = A000960(row); for col > 1, A(row,col) = A278507(row,col-1).
For all n >= 1, A(A278538(n), A278539(n)) = n.
EXAMPLE
The top left corner of the array:
1, 2, 4, 6, 8, 10, 12, 14, 16, 18
3, 5, 11, 17, 23, 29, 35, 41, 47, 53
7, 9, 21, 33, 45, 57, 69, 81, 93, 105
13, 15, 37, 55, 75, 97, 115, 135, 157, 175
19, 25, 51, 85, 111, 145, 171, 205, 231, 265
27, 31, 73, 121, 159, 199, 243, 283, 327, 367
39, 43, 99, 151, 211, 267, 319, 379, 433, 487
49, 61, 127, 193, 271, 343, 421, 483, 559, 631
63, 67, 163, 247, 339, 427, 519, 607, 691, 793
79, 87, 187, 303, 403, 523, 639, 739, 853, 963
PROG
(Scheme)
(define (A278505 n) (A278505bi (A002260 n) (A004736 n)))
(define (A278505bi row col) (if (= 1 col) (A000960 row) (A278507bi row (- col 1)))) ;; Code for A278507bi given in A278507.
CROSSREFS
Inverse: A278506.
Transpose: A278503.
Column 1: A000960, column 2: A100287 (apart from its initial 1), A099259 (differences).
Cf. A278538 (row index of n), A278539 (column index of n).
Cf. also arrays A278507 and A278511 (different variants).
Cf. also A255545 (an analogous array constructed for Lucky sieve).
Sequence in context: A369281 A266637 A370496 * A278506 A255546 A358874
KEYWORD
nonn,tabl
AUTHOR
Antti Karttunen, Nov 23 2016
STATUS
approved

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Last modified August 29 23:09 EDT 2024. Contains 375519 sequences. (Running on oeis4.)