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A338928 Record values of A338565.

%I A338928 #6 Nov 15 2020 22:34:06
%S A338928 1,2,3,4,7,17,21,38,58,82,148,174,176,360,362,479,846,1289,1934,2196,
%T A338928 3315,4326,5701,8225,8910,9507,11346,14262,19832,25072,30279,34638,
%U A338928 46714,67520,78082,82112,94916,107902,175532,195760,273164,275892,443284,479324
%N A338928 Record values of A338565.
%F A338928 a(n) = A338565(A338927(n)).
%p A338928 ispali:= proc(n) local L;
%p A338928   L:= convert(n,base,10);
%p A338928   evalb(L = ListTools:-Reverse(L))
%p A338928 end proc:
%p A338928 N:= 200000: # for terms <= N
%p A338928 Palis:= select(ispali, {$2..N}):
%p A338928 A338565:= Vector(N):
%p A338928 A338565[1]:= 1:
%p A338928 R:= 1: bestv:= 1:
%p A338928 A[1]:= 1:
%p A338928 for n from 2 to N do
%p A338928   A[n]:=  add(A[n/d], d= numtheory:-divisors(n) intersect Palis);
%p A338928     if A[n] > bestv then bestv:= A[n]; R:= R, bestv
%p A338928 od:
%p A338928 R;
%t A338928 Block[{a}, a[n_] := If[n == 1, n, Sum[If[(d < n && PalindromeQ[n/d]), a[d], 0], {d, Divisors[n]}]]; Union@ FoldList[Max, Array[a, 10^4]]] (* _Michael De Vlieger_, Nov 15 2020 *)
%Y A338928 Cf. A338565, A338927.
%K A338928 nonn
%O A338928 1,2
%A A338928 _Robert Israel_, Nov 15 2020