A084024 Triangle read by rows in which row n gives n smallest n-digit multiples of n that are palindromes.
1, 22, 44, 111, 141, 171, 2112, 2332, 2552, 2772, 50005, 50105, 50205, 50305, 50405, 201102, 204402, 207702, 210012, 213312, 216612, 1002001, 1009001, 1011101, 1018101, 1020201, 1027201, 1036301, 21100112, 21111112, 21122112, 21133112, 21144112, 21155112, 21166112, 21177112
Offset: 1
Examples
1 22 44 111 141 171 2112 2332 2552 2772 ...
Programs
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Mathematica
snm[n_]:=Module[{a=Floor[10^(n-1)],b=Floor[10^n-1]},Select[ Select[ Range[ a,b],Divisible[#,n]&&IntegerLength[#]==n&],PalindromeQ,n]]; Array[ snm,8]//Flatten (* Harvey P. Dale, Aug 23 2020 *) -
PARI
isok(k, n) = my(d=digits(k*n)); (#d == n) && (Vecrev(d) == d); row(n) = {my(v=vector(n), k = ceil(10^(n-1)/n)); for (i=1, n, while(! isok(k, n), k++); v[i] = k*n; k++;); v;} \\ Michel Marcus, Mar 28 2020
Formula
Extensions
Corrected and extended by Ray Chandler, Jun 12 2003
More terms from Michel Marcus, Mar 28 2020