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A178681
a(n) = 6^n + 6.
2
7, 12, 42, 222, 1302, 7782, 46662, 279942, 1679622, 10077702, 60466182, 362797062, 2176782342, 13060694022, 78364164102, 470184984582, 2821109907462, 16926659444742, 101559956668422, 609359740010502
OFFSET
0,1
FORMULA
a(n) = 6*(a(n-1)-5), n > 0.
a(n) = 7*a(n-1) - 6*a(n-2).
a(n) = 6*A062394(n-1), n > 0.
G.f.: (7-37*x)/((1-x)*(1-6*x)). - Klaus Brockhaus, Dec 27 2010
a(n) = A000400(n) + 6. - Michel Marcus, Nov 23 2013
E.g.f.: exp(6*x) + 6*exp(x). - G. C. Greubel, Jan 26 2019
MATHEMATICA
LinearRecurrence[{7, -6}, {7, 12}, 41] (* or *) 6^Range[0, 40]+6 (* Harvey P. Dale, Aug 11 2011 *)
PROG
(Magma) [ 6^n+6: n in [0..25] ];
(PARI) for(n=0, 25, print1(6^n+6, ", ")) \\ Edward Jiang, Nov 22 2013
(Sage) [6^n +6 for n in range(25)] # G. C. Greubel, Jan 26 2019
(GAP) List([0..25], n -> 6^n + 6); # G. C. Greubel, Jan 26 2019
CROSSREFS
Cf. A000400, A052934 (first differences).
Sequence in context: A218554 A113499 A335579 * A194264 A192779 A108238
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Dec 25 2010
STATUS
approved