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A155724 Triangle read by rows: T(m,n) = 2mn + m + n - 4. 6
0, 3, 8, 6, 13, 20, 9, 18, 27, 36, 12, 23, 34, 45, 56, 15, 28, 41, 54, 67, 80, 18, 33, 48, 63, 78, 93, 108, 21, 38, 55, 72, 89, 106, 123, 140, 24, 43, 62, 81, 100, 119, 138, 157, 176, 27, 48, 69, 90, 111, 132, 153, 174, 195, 216, 30, 53, 76, 99, 122, 145, 168, 191, 214, 237, 260 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
2*T(m,n)+9 = (2m+1)*(2n+1). - Vincenzo Librandi, Nov 18 2012
First column: A008585; second column: A016885; third column: A017053; fourth column: 9*A020705. - Vincenzo Librandi, Nov 18 2012
LINKS
Vincenzo Librandi, Rows n = 1..100, flattened
FORMULA
T(m,n) = A154685(m,n) - 8. - L. Edson Jeffery, Oct 12 2012
EXAMPLE
Triangle begins:
0;
3, 8;
6, 13, 20;
9, 18, 27, 36;
12, 23, 34, 45, 56;
15, 28, 41, 54, 67, 80;
18, 33, 48, 63, 78, 93, 108;
21, 38, 55, 72, 89, 106, 123, 140;
24, 43, 62, 81, 100, 119, 138, 157, 176;
27, 48, 69, 90, 111, 132, 153, 174, 195, 216;
MATHEMATICA
Flatten[Table[2 n m + m + n - 4, {n, 10}, {m, n}]] (* Vincenzo Librandi, Mar 01 2012 *)
PROG
(Magma) /* Triangle: */ [[2*m*n+m+n-4: m in [1..n]]: n in [1..10]]; // Bruno Berselli, Aug 31 2012
CROSSREFS
All terms are in A155723.
Sequence in context: A371472 A295573 A080939 * A289485 A304299 A221951
KEYWORD
nonn,tabl,easy
AUTHOR
Vincenzo Librandi, Jan 25 2009
EXTENSIONS
Edited by N. J. A. Sloane, Jun 23 2010
STATUS
approved

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Last modified July 21 14:09 EDT 2024. Contains 374474 sequences. (Running on oeis4.)