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A089574 Column 4 of an array closely related to A083480. (Both arrays have shape sequence A083479). 10
5, 32, 113, 299, 664, 1309, 2366, 4002, 6423, 9878, 14663, 21125, 29666, 40747, 54892, 72692, 94809, 121980, 155021, 194831, 242396, 298793, 365194, 442870, 533195, 637650, 757827, 895433, 1052294, 1230359, 1431704, 1658536, 1913197 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Columns 1 through 3 are A000124, A000330 and A086602. The diagonals are finite and sum to A047970.

Values appear to be a transformation of A006468 (rooted planar maps). Also known as well-labeled trees (cf. A000168).

First differences of the conjectured polynomial formula for A006468. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 26 2010]

LINKS

Index to sequences with linear recurrences with constant coefficients, signature (6,-15,20,-15,6,-1). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 26 2010]

FORMULA

Row sums are powers of 2.

Equals A000330 + A006011 + A034263

a(n)= +6*a(n-1) -15*a(n-2) +20*a(n-3) -15*a(n-4) +6*a(n-5) -a(n-6). G.f.: x*(5+2*x-4*x^2+x^3)/(x-1)^6. a(n) = A000330(n)+A006011(n+1)+A034263(n-1) = n*(n+1)*(4*n^3+51*n^2+159*n+86)/120. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 26 2010]

EXAMPLE

The array begins

1

2

4

7 1

11 5

16 14 2

22 30 12

29 55 39 5

37 91 95 32 1

CROSSREFS

Cf. A006468, A000079.

Cf. A105552.

Cf. A000330, A006011 and A034261.

Sequence in context: A073694 A101966 A184536 * A077207 A001589 A177467

Adjacent sequences:  A089571 A089572 A089573 * A089575 A089576 A089577

KEYWORD

nonn

AUTHOR

Alford Arnold (Alford1940(AT)aol.com), Dec 29 2003; extended May 04 2005

EXTENSIONS

Extended beyond a(8) by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 26 2010

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Last modified February 17 23:43 EST 2012. Contains 206085 sequences.