a(n) is the least number having exactly n representations as a product of two palindromes.

Terms

a(0) =13a(1) =1a(2) =4a(3) =44a(4) =66a(5) =484a(6) =4444a(7) =7326a(8) =6666a(9) =48884a(10) =73326a(11) =493284a(12) =888888a(13) =666666a(14) =5426124a(15) =4888884a(16) =6672666a(17) =7333326a(18) =44888844a(19) =73399326a(20) =246888642a(21) =67333266a(22) =4073662593a(23) =4893772884a(24) =4533773244a(25) =6800659866a(26) =2715775062a(27) =1481331852a(28) =493777284a(29) =740665926