login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A140648 Triangle T(n,m) which can create A140642 without help of Jacobsthal numbers. 0
1, 2, 0, 4, 1, 0, 8, 2, 0, 1, 16, 4, 1, 0, 2, 32, 8, 2, 0, 1, 4, 64, 16, 4, 1, 0, 2, 8, 128, 32, 8, 2, 0, 1, 4, 16, 256, 64, 16, 4, 1, 0, 2, 8, 32, 512, 128, 32, 8, 2, 0, 1, 4, 16, 64 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

This triangle T(.,.) provides the additional terms if A140642 is constructed with a Pascal-type recurrence: A140642(n+1,m+1) = A140642(n,m) + A140642(n,m+1) + T(n,m+1).

Note almost odd palindromes (of squares) followed by their double.

Examples: 40=16+20+4, 42=20+21+1, 43=21+22+0, 44=22+24+2.

LINKS

Table of n, a(n) for n=0..54.

FORMULA

Southeast diagonals based on A131577 (which is also in A140531). First preceded with 1, 0. Second with 2, 1, 0. Tends towards even palindromes, second part being A131577. Verticals: A000079, A131577, (0, A131577), ... .

EXAMPLE

Triangle begins:

    1;

    2,  0;

    4,  1,  0;

    8,  2,  0,  1;

   16,  4,  1,  0,  2;

   32,  8,  2,  0,  1,  4;

   64, 16,  4,  1,  0,  2,  8;

  128, 32,  8,  2,  0,  1,  4, 16;

CROSSREFS

Cf. A083329 (row sums).

Sequence in context: A255330 A291940 A153345 * A153342 A144258 A056859

Adjacent sequences:  A140645 A140646 A140647 * A140649 A140650 A140651

KEYWORD

nonn,tabl,uned

AUTHOR

Paul Curtz, Jul 09 2008

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 November 22 03:34 EST 2019. Contains 329385 sequences. (Running on oeis4.)