A099165 Palindromic in bases 10 and 32.
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33, 66, 99, 363, 858, 1441, 2882, 5445, 6886, 9449, 15951, 19891, 21012, 29692, 32223, 54945, 369963, 477774, 564465, 585585, 609906, 672276, 717717, 780087, 804408, 912219, 1251521, 2639362, 3825283
Offset: 1
Links
- Ray Chandler and Robert G. Wilson v, Table of n, a(n) for n = 1..115, terms a(88)-a(111) from Ray Chandler.
Crossrefs
Programs
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Mathematica
NextPalindrome[n_] := Block[{l = Floor[ Log[10, n] + 1], idn = IntegerDigits[n]}, If[ Union[idn] == {9}, Return[n + 2], If[l < 2, Return[n + 1], If[ FromDigits[ Reverse[ Take[idn, Ceiling[l/2]] ]] FromDigits[ Take[idn, -Ceiling[l/2]]], FromDigits[ Join[ Take[idn, Ceiling[l/2]], Reverse[ Take[idn, Floor[l/2]] ]]], idfhn = FromDigits[ Take[idn, Ceiling[l/2]]] + 1; idp = FromDigits[ Join[ IntegerDigits[idfhn], Drop[ Reverse[ IntegerDigits[idfhn]], Mod[l, 2]] ]]] ]]]; palQ[n_Integer, base_Integer] := Block[{idn = IntegerDigits[n, base]}, idn == Reverse[idn]]; l = {0}; a = 0; Do[a = NextPalindrome[a]; If[ palQ[a, 32], AppendTo[l, a]], {n, 10000}]; l Select[Range[0, 10^5], PalindromeQ[#] && # == IntegerReverse[#, 32] &] (* Robert Price, Nov 09 2019 *)
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Python
from gmpy2 import digits def palQ(n,b): # check if n is a palindrome in base b s = digits(n,b) return s == s[::-1] def palQgen10(l): # unordered generator of palindromes of length <= 2*l if l > 0: yield 0 for x in range(1,10**l): s = str(x) yield int(s+s[-2::-1]) yield int(s+s[::-1]) A099165_list = sorted([n for n in palQgen10(6) if palQ(n,32)]) # Chai Wah Wu, Nov 25 2014