A075876 - OEIS

%I #16 May 31 2024 22:11:10

%S 0,2,4,12,52,212,852,3412,13652,54612,218452,873812,3495252,13981012

%N Values of m for which A075825(m) = 1.

%C For n > 4 it appears that a(n) = 4*a(n-1) + 4.

%C From _Robert Israel_, Nov 08 2016: (Start)

%C By induction, we have for k >= 0:

%C   A075825((10*4^k-7)/3) = 2^(k+1)

%C   A075825((10*4^k-4)/3) = 1

%C   A075825((10*4^k-1)/3) = 2^(k+1)+1

%C   A075825((20*4^k-8)/3) = 2^(k+1)-1

%C   A075825((20*4^k-5)/3) = 2^(k+1)+1

%C   A075825((20*4^k-1)/3) = 2^(k+1)

%C In particular, this sequence contains b(k) = (10*4^k-4)/3 which is the solution of b(k) = 4*b(k-1)+4 with b(0) = 2.

%C The only terms <= 2*10^7 that are not of that form are 0 and 4. (End)

%Y Cf. A075825.

%K nonn

%O 1,2

%A _John W. Layman_, Oct 16 2002

%E a(10)-a(14) from _Robert Israel_, Nov 08 2016