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A268724 Square array A(i,j) = A006068(i) * A006068(j), read by antidiagonals as A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), ... 5
1, 3, 3, 2, 9, 2, 7, 6, 6, 7, 6, 21, 4, 21, 6, 4, 18, 14, 14, 18, 4, 5, 12, 12, 49, 12, 12, 5, 15, 15, 8, 42, 42, 8, 15, 15, 14, 45, 10, 28, 36, 28, 10, 45, 14, 12, 42, 30, 35, 24, 24, 35, 30, 42, 12, 13, 36, 28, 105, 30, 16, 30, 105, 28, 36, 13, 8, 39, 24, 98, 90, 20, 20, 90, 98, 24, 39, 8, 9, 24, 26, 84, 84, 60, 25, 60, 84, 84, 26, 24, 9 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..15051; the first 173 antidiagonals of the array

FORMULA

A(i,j) = A006068(i) * A006068(j)

A(i,j) = A006068(A268725(i,j)).

EXAMPLE

The top left [1 .. 15] x [1 .. 15] section of the array:

   1,  3,  2,  7,   6,  4,  5,  15,  14,  12,  13,   8,   9,  11,  10

   3,  9,  6,  21, 18, 12, 15,  45,  42,  36,  39,  24,  27,  33,  30

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

   7, 21, 14,  49, 42, 28, 35, 105,  98,  84,  91,  56,  63,  77,  70

   6, 18, 12,  42, 36, 24, 30,  90,  84,  72,  78,  48,  54,  66,  60

   4, 12,  8,  28, 24, 16, 20,  60,  56,  48,  52,  32,  36,  44,  40

   5, 15, 10,  35, 30, 20, 25,  75,  70,  60,  65,  40,  45,  55,  50

  15, 45, 30, 105, 90, 60, 75, 225, 210, 180, 195, 120, 135, 165, 150

  14, 42, 28,  98, 84, 56, 70, 210, 196, 168, 182, 112, 126, 154, 140

  12, 36, 24,  84, 72, 48, 60, 180, 168, 144, 156,  96, 108, 132, 120

  13, 39, 26,  91, 78, 52, 65, 195, 182, 156, 169, 104, 117, 143, 130

   8, 24, 16,  56, 48, 32, 40, 120, 112,  96, 104,  64,  72,  88,  80

   9, 27, 18,  63, 54, 36, 45, 135, 126, 108, 117,  72,  81,  99,  90

  11, 33, 22,  77, 66, 44, 55, 165, 154, 132, 143,  88,  99, 121, 110

  10, 30, 20,  70, 60, 40, 50, 150, 140, 120, 130,  80,  90, 110, 100

PROG

(Scheme)

(define (A268724 n) (A268724bi (A002260 n) (A004736 n)))

(define (A268724bi row col) (* (A006068 row) (A006068 col)))

CROSSREFS

Cf. A268725.

Cf. A006068 (row 1, column 1).

Cf. A268716 (row 3, column 3).

Cf. A268721 (the antidiagonal sums).

Cf. also A268714.

Sequence in context: A200770 A265965 A192787 * A248569 A214101 A286952

Adjacent sequences:  A268721 A268722 A268723 * A268725 A268726 A268727

KEYWORD

nonn,tabl

AUTHOR

Antti Karttunen, Feb 13 2016

STATUS

approved

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Last modified January 26 20:02 EST 2022. Contains 350599 sequences. (Running on oeis4.)