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A275535
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a(n) = the smallest positive multiple of n that is the sum of more than 1 consecutive positive integers.
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0
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3, 6, 3, 12, 5, 6, 7, 24, 9, 10, 11, 12, 13, 14, 15, 48, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 96, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 192, 65, 66, 67
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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a(n) = 3*n if n is a power of 2, a(n) = n else. - Alois P. Heinz, Aug 01 2016
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EXAMPLE
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n=1, 3=1+2; n=2, 6 = 1 + 2 + 3; n=3, 3 = 1 + 2; n=4, 12 = 3 + 4 + 5;
n=5, 5=2+3; n=6, 6=1+2+3; n=7, 7=3+4; n=8, 24=7+ 8+ 9;
n=9, 9=4+5; n=10, 10=1+2+3+4; n=11, 11=5+6; n=12, 12=3+4+5;
n=13, 13=6+7; n=14, 14=2+3+4+5; n=15, 15=7+8.
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MAPLE
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a:= n-> `if`(2^ilog2(n)=n, 3*n, n):
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PROG
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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