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A261066
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(7^(2^n) - 1) / 2^(n+2).
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1
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OFFSET
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1,1
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COMMENTS
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(m^(2^n)-1)/2^(n+2) is an integer for any odd value of m and n>0.
The next term, a(7), has 106 decimal digits.
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LINKS
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FORMULA
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a(n) == 150 (mod 10^4) for all n > 1. - M. F. Hasler, Aug 11 2015
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EXAMPLE
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a(3) = (7^8 - 1)/2^5 = 180150.
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MATHEMATICA
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PROG
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(PARI) first(m)=vector(m, i, (7^(2^i)-1)/2^(i+2)); /* Anders Hellström, Aug 08 2015 */
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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