A000217Triangular numbers: a(n) = binomial(n+1,2) = n*(n+1)/2 = 0 + 1 + 2 + ... + n.
0, 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 66, 78, 91, 105, 120, …
The first 2 terms appear at position 167.
…5358979323846264338327950288419716939937510582097…
…59408128481117450284102701938521105559644622948954…
…947826848260147699090264013639443745530506820349625…
…9478268482601476990902640136394437455305068203496252…
…487575529409902873248194013610819428190470689114022142…
…11355467598865710802583701361015288074751841131809263769…
| terms | string | first position | occurrences |
|---|---|---|---|
| 1 | 0 | 32 | 99,993,942 |
| 2 | 01 | 167 | 9,998,250 |
| 3 | 013 | 2,079 | 1,000,932 |
| 4 | 0136 | 2,079 | 100,221 |
| 5 | 013610 | 1,972,610 | 1,010 |
| 6 | 01361015 | 104,349,019 | 6 |
| 7 | 0136101521 | not within 1,000,000,000 | 0 |
| 8 | 013610152128 | not within 1,000,000,000 | 0 |
Searched the first 1,000,000,000 digits. Strings longer than 12 digits are not indexed.