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A028984
Palindromes whose sum of divisors is odd.
0
2, 4, 8, 9, 121, 242, 484, 676, 10201, 12321, 14641, 20402, 24642, 40804, 44944, 69696, 94249, 698896, 1002001, 1234321, 2004002, 2138312, 2468642, 4008004, 5221225, 6948496, 85099058, 100020001, 102030201, 104060401, 121242121
OFFSET
1,1
MATHEMATICA
Select[Range[2, 122*10^6], PalindromeQ[#]&&OddQ[DivisorSigma[1, #]]&] (* Harvey P. Dale, Aug 01 2020 *)
CROSSREFS
Sequence in context: A088274 A118418 A074810 * A294369 A302907 A319561
KEYWORD
nonn,base
STATUS
approved