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A283716
Row n=3 of A283674.
2
3, 32, 746, 19748, 531698, 14349932, 387424586, 10460369588, 282429602018, 7625597747132, 205891133143226, 5559060570749828, 150094635313776338, 4052555153086085132, 109418989131780794666, 2954312706551907440468, 79766443076876804830658
OFFSET
0,1
FORMULA
G.f.: (3 - 64*x + 139*x^2)/((1 - x)*(1 - 4*x)*(1 - 27*x)).
a(n) = 32*a(n-1) - 139*a(n-2) + 108*a(n-3) for n > 2.
a(n) = 1 + 4^n + 27^n.
MATHEMATICA
Table[1 + 4^n + 27^n, {n, 0, 20}] (* Bruno Berselli, Mar 15 2017 *)
CoefficientList[Series[(3 - 64*x + 139*x^2)/((1 - x)*(1 - 4*x)*(1 - 27*x)), {x, 0, 17}], x] (* Indranil Ghosh, Mar 15 2017 *)
PROG
(PARI) Vec((3 - 64*x + 139*x^2)/((1 - x)*(1 - 4*x)*(1 - 27*x)) + O(x^17)) \\ Indranil Ghosh, Mar 15 2017
(PARI) a(n) = 1 + 4^n + 27^n \\ Indranil Ghosh, Mar 15 2017
(Python) def A283716(n): return 1 + 4**n + 27**n # Indranil Ghosh, Mar 15 2017
CROSSREFS
Cf. A283674.
Sequence in context: A129431 A373857 A297558 * A373875 A352019 A374574
KEYWORD
nonn,easy
AUTHOR
Seiichi Manyama, Mar 15 2017
EXTENSIONS
Extended by Bruno Berselli, Mar 15 2017
STATUS
approved