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 A145302 a(n) = ((7 + sqrt(7))^n + (7 - sqrt(7))^n)/2. 6
 1, 7, 56, 490, 4508, 42532, 406112, 3899224, 37532432, 361686640, 3487250816, 33630672544, 324364881344, 3128620091968, 30177356271104, 291080943932800, 2807684251672832, 27082179878242048, 261227779725129728 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Binomial transform is A152265, inverse binomial transform is A146966. LINKS Index entries for linear recurrences with constant coefficients, signature (14, -42). FORMULA From R. J. Mathar, Oct 10 2008: (Start) a(n) = 14*a(n-1) - 42*a(n-2). G.f.: (1-7x)/(1-14x+42x^2). (End) a(n) = Sum_{k=0..n} 7^k*A098158(n,k). - Philippe Deléham, Oct 14 2008 PROG (MAGMA) Z:= PolynomialRing(Integers()); N:=NumberField(x^2-7); S:=[ ((7+r7)^n+(7-r7)^n)/2: n in [0..18] ]; [ Integers()!S[j]: j in [1..#S] ]; // Klaus Brockhaus, Oct 20 2008, Jul 09 2009 CROSSREFS Cf. A098158, A152265, A146966. Sequence in context: A264912 A323216 A024091 * A233669 A265233 A165322 Adjacent sequences:  A145299 A145300 A145301 * A145303 A145304 A145305 KEYWORD nonn AUTHOR Al Hakanson (hawkuu(AT)gmail.com), Oct 06 2008 EXTENSIONS More terms from R. J. Mathar, Oct 10 2008 Edited by Klaus Brockhaus, Jul 09 2009 STATUS approved

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Last modified August 7 06:02 EDT 2020. Contains 336274 sequences. (Running on oeis4.)