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

 

Logo

Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A141533 The first subdiagonal of the array of A141425 and its higher order differences. 2
1, -1, -2, 23, 28, -7, 22, 251, 376, 149, 658, 3143, 5188, 4913, 13102, 42611, 75376, 101549, 232618, 612863, 1137148, 1831433, 3928582, 9185771, 17574376, 31162949, 64717378, 141392183, 275609908, 515347553, 1052218462, 2212053731, 4359537376, 8396224349 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..34.

FORMULA

a(2*n)+a(2*n+1)= 0, 21, 21, 273, 525, 3801,... (multiples of 21).

a(n)= +a(n-1) -a(n-2) +3*a(n-3) +6*a(n-4). G.f.: x*(1-2*x+21*x^3)/((1-2*x) * (1+x) * (3*x^2+1)). [R. J. Mathar, Nov 22 2009]

a(n)= (3*(-1)^n+2^n-A128019(n+1))/2. [R. J. Mathar, Nov 22 2009]

EXAMPLE

A141425 and its first, second, third differences etc. in followup rows define an array T(n,m):

..1...2...4...5...7...8...1...2...4...5...

..1...2...1...2...1..-7...1...2...1...2...

..1..-1...1..-1..-8...8...1..-1...1..-1...

.-2...2..-2..-7..16..-7..-2...2..-2..-7...

..4..-4..-5..23.-23...5...4..-4..-5..23...

.-8..-1..28.-46..28..-1..-8..-1..28.-46...

..7..29.-74..74.-29..-7...7..29.-74..74...

.22.-103.148.-103..22..14..22.-103.148.-103...

-125.251.-251.125..-8...8.-125.251.-251.125...

376.-502.376.-133..16.-133.376.-502.376.-133...

Then a(n) = T(n+1,n) .

CROSSREFS

Sequence in context: A086557 A042797 A041649 * A045391 A154758 A156614

Adjacent sequences:  A141530 A141531 A141532 * A141534 A141535 A141536

KEYWORD

sign

AUTHOR

Paul Curtz, Aug 12 2008

EXTENSIONS

Edited and extended by R. J. Mathar, Nov 22 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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified November 21 13:53 EST 2017. Contains 295001 sequences.