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A354837
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Odd numbers k such that gcd(k, A007088(k)) != 1.
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2
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21, 33, 63, 69, 81, 99, 111, 123, 159, 165, 183, 189, 203, 207, 219, 231, 237, 243, 249, 259, 261, 273, 297, 303, 315, 321, 363, 399, 411, 423, 429, 435, 441, 459, 483, 489, 495, 513, 543, 561, 567, 573, 585, 591, 603, 615, 621, 627, 633, 663, 669, 693, 707, 711
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OFFSET
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1,1
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LINKS
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EXAMPLE
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k = 33; gcd(33,A007088(33)) = gcd(33, 100001) = 11, thus k = 33 is a term.
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MATHEMATICA
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Select[Range[1, 700, 2], ! CoprimeQ[#, FromDigits[IntegerDigits[#, 2]]] &] (* Amiram Eldar, Jun 08 2022 *)
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PROG
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(PARI) isok(k) = (k%2) && (gcd(k, fromdigits(binary(k))) != 1); \\ Michel Marcus, Jun 09 2022
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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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