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A028558
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Numbers k such that k*(k+5) is a palindrome.
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1
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0, 1, 6, 18, 24, 202, 203, 814, 2067, 2178, 2207, 20402, 25116, 64493, 82566, 207067, 2040402, 2187142, 2233097, 6887078, 79585891, 211313148, 249281986, 8161664181, 22222222222, 26331005924, 81294635989, 2008491060208, 2048192235518, 2228557243297, 2471952825156
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OFFSET
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1,3
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COMMENTS
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a(34) > 10^13
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LINKS
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PROG
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(Python)
from itertools import count, islice
def ispal(n): s = str(n); return s == s[::-1]
def agen():
for k in count(0):
if ispal(k*(k+5)):
yield k
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CROSSREFS
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KEYWORD
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nonn,base,changed
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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