1166220

Appears in sequences

• Tribonacci numbers: a(n) = a(n-1) + a(n-2) + a(n-3) with a(0)=0, a(1)=1, a(2)=0.at n=26A001590
• Consider the sequence of 4-tuples {0,a,b,c} (c>=a+b; a,b,c>0) which have the smallest integer 'c' required to reach {k,k,k,k} in n steps under map {r,s,t,u}->{|r-s|,|s-t|,|t-u|,|u-r|}. This sequence gives the second term 'a' of these quadruples.at n=40A034803
• Consider the sequence of 4-tuples {0,a,b,c} (c>=a+b; a,b,c>0) which have the smallest integer 'c' required to reach {k,k,k,k} in n steps under map {r,s,t,u}->{|r-s|,|s-t|,|t-u|,|u-r|}. This sequence gives the third term 'b' of these quadruples.at n=38A034804
• a(n) = Sum_{k=0..n} T(n, k), array T as in A047080.at n=23A047081
• Tribonacci sequences A000073 and A001590 interleaved.at n=47A213816
• Number of n X 2 0..3 arrays x(i,j) with each element horizontally or vertically next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero.at n=12A231057
• Numbers of the form t_n or t_n + t_{n+1} where {t_n} are the tribonacci numbers A000073.at n=45A308189