2145013

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=27A001590
• Consider all quadruples {a,b,c,d} which reach {k,k,k,k} in n steps under map {a,b,c,d}->{|a-b|,|b-c|,|c-d|,|d-a|}; look at max{a,b,c,d}; sequence gives minimal value of this.at n=37A045794
• a(n) = Sum_{k=0..n} T(n, k), array T as in A047080.at n=24A047081
• Minimum value t such that all quadruples of Diffy_length >= n have a maximal value >= t.at n=39A065678
• Expansion of (1-x)/(1+x-x^2+x^3).at n=24A078042
• Coefficient of x in the reduction of the polynomial (x^2 + x + 1)^n by x^3 -> x^2 + x + 1.at n=9A192807
• Numbers of the form t_n or t_n + t_{n+1} where {t_n} are the tribonacci numbers A000073.at n=47A308189