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A163672 Triangle T(n,m) = 2mn + m + n + 7 read by rows. 4
11, 14, 19, 17, 24, 31, 20, 29, 38, 47, 23, 34, 45, 56, 67, 26, 39, 52, 65, 78, 91, 29, 44, 59, 74, 89, 104, 119, 32, 49, 66, 83, 100, 117, 134, 151, 35, 54, 73, 92, 111, 130, 149, 168, 187, 38, 59, 80, 101, 122, 143, 164, 185, 206, 227, 41, 64, 87, 110, 133, 156, 179 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

2*T(n,n) - 13 = (2n+1)^2.

The numbers 2*T(m,n)-13 =(2*n+1)*(2*m+1) are not prime. Also: first column: A016789; second column: A016897; third column: A017017; fourth column: A017185. - Vincenzo Librandi, Nov 20 2012

LINKS

Vincenzo Librandi, Rows n = 1..100, flattened

FORMULA

T(n,m) = A163674(n,m)-2 = A163657(n,m)-1.

EXAMPLE

Triangle begins:

  11;

  14,  19;

  17,  24,  31;

  20,  29,  38,  47;

  23,  34,  45,  56,  67;

  26,  39,  52,  65,  78,  91;

  29,  44,  59,  74,  89, 104, 119;

  32,  49,  66,  83, 100, 117, 134, 151;

MATHEMATICA

t[n_, k_]:=2 n*k + n + k + 7; Table[t[n, k], {n, 15}, {k, n}]//Flatten (* Vincenzo Librandi, Nov 20 2012 *)

PROG

(MAGMA) [2*n*k + n + k + 7: k in [1..n], n in [1..11]]; // Vincenzo Librandi, Nov 20 2012

(PARI) for(n=1, 10, for(m=1, n, print1(2*m*n + m + n + 7, ", "))) \\ G. C. Greubel, Aug 02 2017

CROSSREFS

Cf. A016789, A016897, A017017, A017185, A153049, A163674, A163657.

Sequence in context: A159020 A015830 A242098 * A216580 A114948 A191933

Adjacent sequences:  A163669 A163670 A163671 * A163673 A163674 A163675

KEYWORD

nonn,easy,tabl

AUTHOR

Vincenzo Librandi, Aug 03 2009

EXTENSIONS

Edited by R. J. Mathar, Oct 12 2009

STATUS

approved

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Last modified April 19 06:30 EDT 2019. Contains 322237 sequences. (Running on oeis4.)