A342347 a(1) = 7, a(n) = smallest palindromic nontrivial multiple of a(n-1) containing all decimal digits of a(n-1).
7, 77, 1771, 178871, 1788888871, 2188118778118812, 218811879999999978118812, 2188118799999999999999999999999978118812
Offset: 1
Examples
a(3) = 1771 is a palindromic multiple of a(2) = 77 and contains two '7', all the digits of a(2).
Extensions
a(8) from Max Alekseyev, Feb 15 2024
Comments