A068641
Smallest n-digit palindromic triangular number, or 0 if no such number exists.
Original entry on oeis.org
1, 55, 171, 3003, 15051, 617716, 1269621, 35133153, 178727871, 1264114621, 13953435931, 0, 1313207023131, 19895044059891, 114401848104411, 1250444114440521, 11121736463712111, 357961407704169753
Offset: 1
a(4) = 3003 = 77*78/2 is the smallest 4-digit palindromic triangular number.
a(12) = 0 as no 12-digit palindromic triangular number exists.
A068643
Largest n-digit palindromic triangular number, or 0 if no such number exists.
Original entry on oeis.org
6, 66, 666, 8778, 66066, 828828, 6295926, 61477416, 178727871, 6172882716, 87350505378, 0, 68742000024786, 82078700787028, 684866959668486, 8208268228628028, 67898244444289876, 514816979979618415
Offset: 1
a(4) = 8778 = 132*133/2 is the largest 4-digit palindromic triangular number.
a(12) = 0 as no 12-digit palindromic triangular number exists.
A068644
Index of the largest n-digit palindromic triangular number, or 0 if no such number exists.
Original entry on oeis.org
3, 11, 36, 132, 363, 1287, 3548, 11088, 18906, 111111, 417972, 0, 3707883, 12812392, 37009916, 128127032, 368505751, 1014708805, 3567632391, 11151642876, 36657342048, 104561417190, 417898160427, 1325269593372
Offset: 1
a(4) = 132 as 132*133/2 = 8778 is the largest 4-digit palindromic triangular number.
a(12) = 0 as no 12-digit palindromic triangular number exists.
Showing 1-3 of 3 results.