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A098353 Multiplication table of the odd numbers read by antidiagonals. 3
1, 3, 3, 5, 9, 5, 7, 15, 15, 7, 9, 21, 25, 21, 9, 11, 27, 35, 35, 27, 11, 13, 33, 45, 49, 45, 33, 13, 15, 39, 55, 63, 63, 55, 39, 15, 17, 45, 65, 77, 81, 77, 65, 45, 17, 19, 51, 75, 91, 99, 99, 91, 75, 51, 19, 21, 57, 85, 105, 117, 121, 117, 105, 85, 57, 21 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
a(n) is also the first row of the denominators of the Gram Matrix generated from the normal equations with inner product of the 2D integral with both ranges -1 to 1 over all even 2D polynomials. Subsequent rows and remaining Gram Matrix rows for other 2D polynomials do not currently appear in the OEIS. - John Spitzer, Feb 13 2020
LINKS
FORMULA
a(n) = A204022(n,k) * A157454(n,k). - Ridouane Oudra, Jul 20 2019
EXAMPLE
Array begins:
1, 3, 5, 7, 9, 11 ...
3, 9, 15, 21, 27, 33 ...
5, 15, 25, 35, 45, 55 ...
7, 21, 35, 49, 63, 77 ...
9, 27, 45, 63, 81, 99 ...
11, 33, 55, 77, 99, 121 ...
MAPLE
seq(seq(max(2*k-1, 2*(n-k)+1)*min(2*k-1, 2*(n-k)+1), k = 1..n), n = 1..12); # G. C. Greubel, Aug 16 2019
MATHEMATICA
Table[Max[2*k-1, 2*(n-k)+1]*Min[2*k-1, 2*(n-k)+1], {n, 0, 12}, {k, 0, n} ]//Flatten (* G. C. Greubel, Jul 23 2019 *)
PROG
(PARI) {T(n, k) = max(2*k-1, 2*(n-k)+1)*min(2*k-1, 2*(n-k)+1)};
for(n=1, 12, for(k=1, n, print1(T(n, k), ", "))) \\ G. C. Greubel, Jul 23 2019
(Magma) [[Max(2*k-1, 2*(n-k)+1)*Min(2*k-1, 2*(n-k)+1): k in [1..n]]: n in [1..12]]; // G. C. Greubel, Jul 23 2019
(Sage) [[max(2*k-1, 2*(n-k)+1)*min(2*k-1, 2*(n-k)+1) for k in (1..n)] for n in (1..12)] # G. C. Greubel, Jul 23 2019
(GAP) Flat(List([1..12], n-> List([1..n], k-> Maximum(2*k-1, 2*(n-k)+1) *Minimum(2*k-1, 2*(n-k)+1) ))) # G. C. Greubel, Jul 23 2019
CROSSREFS
Sequence in context: A213678 A293676 A303714 * A073060 A183526 A337562
KEYWORD
nonn,tabl
AUTHOR
Douglas Stones (dssto1(AT)student.monash.edu.au), Sep 04 2004
STATUS
approved

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Last modified April 24 13:58 EDT 2024. Contains 371960 sequences. (Running on oeis4.)