login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A183108 Numbers m such that sum of divisors of m and sum of palindromic divisors of m are both palindromic. 0

%I #10 Feb 20 2023 07:51:55

%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 m such that sum of divisors of m and sum of palindromic divisors of m 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

%Y Cf. A000203, A088000.

%K nonn,base

%O 1,2

%A _Jaroslav Krizek_, Dec 25 2010

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 24 07:54 EDT 2024. Contains 371922 sequences. (Running on oeis4.)