

A187179


Number of nontrivial compositions of differential operations and directional derivative of the nth order on the space R^10.


0



7, 7, 8, 9, 11, 14, 19, 27, 40, 61, 95, 150, 239, 383, 616, 993, 1603, 2590, 4187, 6771, 10952, 17717, 28663, 46374, 75031, 121399, 196424, 317817, 514235, 832046, 1346275, 2178315, 3524584, 5702893, 9227471, 14930358, 24157823
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..37.
Ivana Jovović and Branko Malešević, Some enumerations of nontrivial composition of the differential operations and the directional derivative, Notes on Number Theory and Discrete Mathematics, Vol. 23, 2017, No. 1, 2838.
Index entries for linear recurrences with constant coefficients, signature (2,0,1).


FORMULA

a(n) = A000045(n) + 6.
a(n) = 2*a(n1)a(n3). G.f.: x*(6*x^2+7*x7) / ((x1)*(x^2+x1)). [Colin Barker, Dec 14 2012]


MATHEMATICA

LinearRecurrence[{2, 0, 1}, {7, 7, 8}, 40] (* Harvey P. Dale, Apr 29 2015 *)


CROSSREFS

Cf. A000045.
Sequence in context: A024818 A076236 A072520 * A110941 A182470 A157290
Adjacent sequences: A187176 A187177 A187178 * A187180 A187181 A187182


KEYWORD

nonn,easy


AUTHOR

Branko Malesevic, Mar 06 2011


STATUS

approved



