A084024 - OEIS

%I #15 Aug 23 2020 15:30:33

%S 1,22,44,111,141,171,2112,2332,2552,2772,50005,50105,50205,50305,

%T 50405,201102,204402,207702,210012,213312,216612,1002001,1009001,

%U 1011101,1018101,1020201,1027201,1036301,21100112,21111112,21122112,21133112,21144112,21155112,21166112,21177112

%N Triangle read by rows in which row n gives n smallest n-digit multiples of n that are palindromes.

%F T(n, 1) >= A053041(n); T(n, 1) = A083123(n). - _Michel Marcus_, Mar 28 2020

%e 1

%e 22 44

%e 111 141 171

%e 2112 2332 2552 2772

%e ...

%t 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 *)

%o (PARI) isok(k, n) = my(d=digits(k*n)); (#d == n) && (Vecrev(d) == d);

%o 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

%Y Cf. A053041, A083123, A084025, A084026, A084027, A084028.

%K base,nonn,tabl

%O 1,2

%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 23 2003

%E Corrected and extended by _Ray Chandler_, Jun 12 2003

%E More terms from _Michel Marcus_, Mar 28 2020