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A176916
a(n) = 5^n + 5*n + 1.
4
2, 11, 36, 141, 646, 3151, 15656, 78161, 390666, 1953171, 9765676, 48828181, 244140686, 1220703191, 6103515696, 30517578201, 152587890706, 762939453211, 3814697265716, 19073486328221, 95367431640726, 476837158203231, 2384185791015736, 11920928955078241, 59604644775390746
OFFSET
0,1
FORMULA
a(n) = A000351(n) + A008587(n) + 1 = A000351(n) + A016861(n).
From R. J. Mathar, Apr 29 2010: (Start)
a(n) = 7*a(n-1) - 11*a(n-2) + 5*a(n-3).
G.f.: ( -2+3*x+19*x^2 ) / ( (5*x-1)*(x-1)^2 ). (End)
E.g.f.: exp(x)*(1 + exp(4*x) + 5*x). - Stefano Spezia, Aug 19 2024
EXAMPLE
a(3) = 5^3 + 5*3 + 1 = 141.
MATHEMATICA
LinearRecurrence[{7, -11, 5}, {2, 11, 36}, 25] (* Stefano Spezia, Aug 19 2024 *)
PROG
(PARI) a(n)=5^n+5*n+1 \\ Charles R Greathouse IV, Aug 23 2024
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Jonathan Vos Post, Apr 28 2010
EXTENSIONS
First term corrected by several authors, Apr 29 2010
a(22)-a(24) from Stefano Spezia, Aug 19 2024
STATUS
approved