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!)
A247710 Number T(n,k) of tilings of a 5 X n rectangle with pentominoes of any shape and exactly k pentominoes of shape W; triangle T(n,k), n>=0, 0<=k<=max(0,floor((n-2)/2)*2) read by rows. 5
1, 1, 5, 56, 461, 32, 8, 3558, 368, 80, 23966, 3256, 696, 24, 8, 178127, 29564, 6558, 360, 80, 1362597, 266672, 61858, 4852, 770, 24, 8, 10194184, 2361632, 581452, 58732, 8890, 384, 80, 75684682, 20056764, 5220634, 632044, 97174, 5968, 914, 24, 8 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Sum_{k>0} k * T(n,k) = A247743(n).

LINKS

Alois P. Heinz, Rows n = 0..145, flattened

Wikipedia, Pentomino

EXAMPLE

T(4,2) = 8:

._______.        ._______.        ._______.

| ._____|        |_. |_. |        | ._____|

|_| ._| |        | |_. | |        |_| ._| |

| ._| ._|        | | |_| |        | ._| | |

|_|___| |        | |_. |_|        |_| ._| |

|_______| (*2)   |___|___| (*2)   |___|___| (*4)

Triangle T(n,k) begins:

00 :        1;

01 :        1;

02 :        5;

03 :       56;

04 :      461,       32,       8;

05 :     3558,      368,      80;

06 :    23966,     3256,     696,     24,     8;

07 :   178127,    29564,    6558,    360,    80;

08 :  1362597,   266672,   61858,   4852,   770,   24,   8;

09 : 10194184,  2361632,  581452,  58732,  8890,  384,  80;

10 : 75684682, 20056764, 5220634, 632044, 97174, 5968, 914, 24, 8;

CROSSREFS

Row sums give A174249 or A233427(n,5).

Column k=0 gives A247774.

Cf. A247743.

Sequence in context: A288543 A062125 A030060 * A247774 A258490 A255953

Adjacent sequences:  A247707 A247708 A247709 * A247711 A247712 A247713

KEYWORD

nonn,tabf

AUTHOR

Alois P. Heinz, Sep 23 2014

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 16 04:40 EST 2021. Contains 340195 sequences. (Running on oeis4.)