OFFSET
1,1
COMMENTS
It seems that these terms are the only numbers n such that n and n + 1 are in A053696.
LINKS
Colin Barker, Table of n, a(n) for n = 1..700
Index entries for linear recurrences with constant coefficients, signature (26,-25).
FORMULA
a(n) = A003463(2*(n+1)).
a(n) = 26*a(n-1) - 25*a(n-2), a(1) = 156, a(2) = 3906.
G.f.: 6*x*(26-25*x) / ((1-x)*(1-25*x)). - Colin Barker, Aug 24 2016
EXAMPLE
3906 written in base 5 is 111111 and 3907 written in base 62 is 111.
MATHEMATICA
Table[(5^(2 (n + 1)) - 1)/4, {n, 16}] (* or *)
Rest@ CoefficientList[Series[6 x (26 - 25 x)/((1 - x) (1 - 25 x)), {x, 0, 16}], x] (* Michael De Vlieger, Aug 28 2016 *)
PROG
(PARI) Vec(6*x*(26-25*x)/((1-x)*(1-25*x)) + O(x^20)) \\ Colin Barker, Aug 24 2016
(PARI) a(n) = 5^(2*n+2)\4 \\ Charles R Greathouse IV, Aug 28 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Gionata Neri, Aug 07 2016
STATUS
approved