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 A183108 Numbers n such that sum of divisors of n and sum of palindromic divisors of n are both palindromic. 0

%I

%S 1,2,3,4,5,7,43,130,146,166,201,205,211,221,241,244,251,271,274,281,

%T 314,325,365,388,422,433,443,463,489,519,559,633,685,793,827,857,877,

%U 887,1841,2021,2111,2221,2284,2305,2441,2551,2561,2666,2751,2881

%N Numbers n such that sum of divisors of n and sum of palindromic divisors of n are both palindromic.

%C Numbers m such that A000203(m) and A088000(m) are both palindromic.

%e a(8) = 130, divisors of 130: 1, 2, 5, 10, 13, 26, 65, 130; palindromic divisors of 130: 1, 2, 5; A000203(130) = 252, A088000(130) = 8; both numbers are palindromic.

%o (Sage) is_palindrome = lambda n, base=10: n.str(base) == n.str(base)[::-1]

%o A000203 = sigma

%o A088000 = lambda n: sum(d for d in divisors(n) if is_palindrome(d))

%o is_A183108 = lambda n: is_palindrome(A000203(n)) and is_palindrome(A088000(n)) # [D. S. McNeil, Dec 28 2010]

%K nonn,base

%O 1,2

%A _Jaroslav Krizek_, Dec 25 2010

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Last modified December 15 04:23 EST 2019. Contains 329991 sequences. (Running on oeis4.)