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A144650
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Triangle read by rows where T(m,n) = 2m*n + m + n + 1.
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1
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5, 8, 13, 11, 18, 25, 14, 23, 32, 41, 17, 28, 39, 50, 61, 20, 33, 46, 59, 72, 85, 23, 38, 53, 68, 83, 98, 113, 26, 43, 60, 77, 94, 111, 128, 145, 29, 48, 67, 86, 105, 124, 143, 162, 181, 32, 53, 74, 95, 116, 137, 158, 179, 200, 221
(list; table; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| 2*T(m,n)-1 = (2*m+1)*(2*n+1) is never prime.
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FORMULA
| Row sum: sum_(n=1..m) T(m,n) = m(2m+3)(m+1)/2 = A160378(n+1). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 15 2009, Jan 05 2011]
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EXAMPLE
| Triangle begins:
5;
8, 13;
11, 18, 25;
14, 23, 32, 41;
17, 28, 39, 50, 61;
20, 33, 46, 59, 72, 85;
23, 38, 53, 68, 83, 98, 113;
26, 43, 60, 77, 94, 111, 128, 145;
29, 48, 67, 86, 105, 124, 143, 162, 181;
32, 53, 74, 95, 116, 137, 158, 179, 200, 221;
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CROSSREFS
| Cf. A104275
Cf. A003307 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.t), Jan 21 2009]
Sequence in context: A185729 A164128 A078412 * A046038 A070127 A070128
Adjacent sequences: A144647 A144648 A144649 * A144651 A144652 A144653
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KEYWORD
| nonn,tabl,easy
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AUTHOR
| Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Jan 13 2009
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