Fibonacci-like numbers defined by the recurrence T(1)=T(2)=1, T(3)=2 and T(n) = T(n-1) + T(n-2) + T(n-3). more
The tribonacci numbers up to 10
15 :
1,
2,
4,
7,
13,
24,
44,
81,
149,
274,
504,
927,
1705,
3136,
5768,
10609,
19513,
35890,
66012,
121415,
223317,
410744,
755476,
1389537,
2555757,
4700770,
8646064,
15902591,
29249425,
53798080,
98950096,
181997601,
334745777,
615693474,
1132436852,
2082876103,
3831006429,
7046319384,
12960201916,
23837527729,
43844049029,
80641778674,
148323355432,
272809183135,
501774317241,
922906855808,
1697490356184,
3122171529233,
5742568741225,
10562230626642,
19426970897100,
35731770264967,
65720971788709,
120879712950776,
222332455004452,
408933139743937,
752145307699165.
Distribution of the remainders when the numbers in this family are divided by n=2, 3,..., 11. (I took into account 100000 values, from 1 to 2.96⋅1026464).
n\r | 0 | 1 |
2 | 50000 | 50000 | 2 |
3 | 30768 | 46155 | 23077 | 3 |
4 | 37500 | 37500 | 12500 | 12500 | 4 |
5 | 19353 | 19355 | 22581 | 9678 | 29033 | 5 |
6 | 15384 | 23078 | 11539 | 15384 | 23077 | 11538 | 6 |
7 | 25000 | 18750 | 18750 | 6251 | 18750 | 6249 | 6250 | 7 |
8 | 25000 | 25000 | 12500 | 0 | 12500 | 12500 | 0 | 12500 | 8 |
9 | 23076 | 15386 | 7693 | 0 | 15385 | 7692 | 7692 | 15384 | 7692 | 9 |
10 | 9676 | 9678 | 11290 | 4840 | 14519 | 9677 | 9677 | 11291 | 4838 | 14514 | 10 |
11 | 9091 | 9092 | 9093 | 9090 | 9092 | 9090 | 9091 | 9091 | 9090 | 9090 | 9090 |
A pictorial representation of the table above
Imagine to divide the members of this family by a number n and compute the remainders. Should they be uniformly distributed, each remainder from 0 to n-1 would be obtained in about (1/n)-th of the cases. This outcome is represented by a white square. Reddish (resp. bluish) squares represent remainders which appear more (resp. less) frequently than 1/n.