login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A163674 Triangle T(n,m) = 2*m*n + m + n + 9 read by rows. 4
13, 16, 21, 19, 26, 33, 22, 31, 40, 49, 25, 36, 47, 58, 69, 28, 41, 54, 67, 80, 93, 31, 46, 61, 76, 91, 106, 121, 34, 51, 68, 85, 102, 119, 136, 153, 37, 56, 75, 94, 113, 132, 151, 170, 189, 40, 61, 82, 103, 124, 145, 166, 187, 208, 229, 43, 66, 89, 112, 135, 158, 181 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

2*T(m,n) - 17 =(2*n+1)*(2*m+1) and 2*T(n,n) - 17 is a square. Also:

first column:  A112414;

second column: A016861;

third column:  A017041;

fourth column: A017209. [Vincenzo Librandi, Nov 20 2012]

LINKS

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

FORMULA

T(n,m) = A163657(n,m) + 1.

EXAMPLE

Triangle begins:

  13;

  16,  21;

  19,  26,  33;

  22,  31,  40,  49;

  25,  36,  47,  58,  69;

  28,  41,  54,  67,  80,  93;

  31,  46,  61,  76,  91, 106, 121;

  34,  51,  68,  85, 102, 119, 136, 153;

MATHEMATICA

t[n_, k_]:=2 n*k + n + k + 9; Table[t[n, k], {n, 15}, {k, n}]//Flatten (* Vincenzo Librandi, Nov 20 2012 *)

PROG

(MAGMA) [2*n*k + n + k + 9: 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 + 9, ", "))) \\ G. C. Greubel, Aug 02 2017

CROSSREFS

Cf. A016861, A017041, A017209, A112414, A153051, A163657.

Sequence in context: A179202 A159975 A110623 * A280062 A132947 A205876

Adjacent sequences:  A163671 A163672 A163673 * A163675 A163676 A163677

KEYWORD

nonn,easy,tabl

AUTHOR

Vincenzo Librandi, Aug 03 2009

EXTENSIONS

Edited by R. J. Mathar, Oct 12 2009

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 17 15:12 EST 2020. Contains 330958 sequences. (Running on oeis4.)