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A249158
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Palindromic in bases 7 and 29.
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4
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0, 1, 2, 3, 4, 5, 6, 8, 16, 24, 150, 300, 5952, 7752, 7955, 9755, 9958, 11904, 13704, 13907, 14110, 15707, 15910, 392850, 751043, 4585544, 12737804, 12828748, 16380296, 19289406, 19380350, 20228253, 33115710, 395849700, 1339182534
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OFFSET
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1,3
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LINKS
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EXAMPLE
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150 is a term since 150 = 303 base 7 and 150 = 55 base 27.
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MATHEMATICA
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palQ[n_Integer, base_Integer]:=Block[{idn=IntegerDigits[n, base]}, idn==Reverse[idn]]; Select[Range[10^6]-1, palQ[#, 7]&&palQ[#, 29]&]
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PROG
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(Python)
from gmpy2 import digits
def palQ(n, b): # check if n is a palindrome in base b
....s = digits(n, b)
....return s == s[::-1]
def palQgen(l, b): # unordered generator of palindromes in base b of length <= 2*l
....if l > 0:
........yield 0
........for x in range(1, b**l):
............s = digits(x, b)
............yield int(s+s[-2::-1], b)
............yield int(s+s[::-1], b)
A249158_list = sorted([n for n in palQgen(8, 7) if palQ(n, 29)])
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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