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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
1, 2, 3, 4, 5, 7, 43, 130, 146, 166, 201, 205, 211, 221, 241, 244, 251, 271, 274, 281, 314, 325, 365, 388, 422, 433, 443, 463, 489, 519, 559, 633, 685, 793, 827, 857, 877, 887, 1841, 2021, 2111, 2221, 2284, 2305, 2441, 2551, 2561, 2666, 2751, 2881 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

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

LINKS

Table of n, a(n) for n=1..50.

EXAMPLE

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.

PROG

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

A000203 = sigma

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

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

CROSSREFS

Sequence in context: A135709 A263043 A028980 * A096841 A029963 A259389

Adjacent sequences:  A183105 A183106 A183107 * A183109 A183110 A183111

KEYWORD

nonn,base

AUTHOR

Jaroslav Krizek, Dec 25 2010

STATUS

approved

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Last modified November 16 22:05 EST 2019. Contains 329208 sequences. (Running on oeis4.)