Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A120769
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A120769 Dot product sequence, with reversed subsets. +0
2
1, 1, 2, 1, 4, 6, 2, 1, 8, 14, 36, 20, 4, 6, 2, 1, 16, 30, 84, 52, 240, 396, 140, 72, 8, 14, 36, 20, 4, 6, 2, 1 (list; graph; listen)
OFFSET

1,3

COMMENT

A120405 = a dot product sequence, with no reversals. A120770 = partial sums of A120769.

FORMULA

a(1) = 1; then perform n * a(n) on each term in the current string; reverse the order and append to right of current string.

EXAMPLE

a(1) = 1, a(2) = 1, then perform the dot product of (1, 2) and (1, 1) getting (1, 2). We reverse (1, 2) getting (2, 1) which we append to the right of the current string (1, 1), getting (1, 1, 2, 1) for a(1) through a(4). Next, perform the dot product of (1, 2, 3, 4) and (1, 1, 2, 1) getting (1, 2, 6, 4) which we reverse, =

(4, 6, 2, 1). Append to the current string (1, 1, 2, 1), getting (1, 1, 2, 1, 4, 6, 2, 1) for a(1) through a(8). Continue with analogous operations.

CROSSREFS

Cf. A120405, A120768, A120770.

Sequence in context: A079474 A091543 A059575 this_sequence A165604 A111932 A121456

Adjacent sequences: A120766 A120767 A120768 this_sequence A120770 A120771 A120772

KEYWORD

nonn,uned

AUTHOR

Gary W. Adamson (qntmpkt(AT)yahoo.com), Jul 03 2006

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 27 22:38 EST 2009. Contains 167602 sequences.


AT&T Labs Research