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A356150
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a(n) is the sum of the positive integers whose binary expansion appears as a substring in the binary expansion of n or its complement.
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3
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1, 3, 4, 10, 8, 12, 11, 25, 25, 18, 26, 28, 30, 33, 26, 56, 62, 61, 56, 56, 39, 63, 64, 67, 62, 66, 72, 77, 80, 78, 57, 119, 139, 143, 137, 135, 134, 119, 134, 134, 134, 81, 120, 138, 139, 147, 142, 146, 147, 148, 132, 153, 140, 157, 165, 165, 168, 174, 181
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OFFSET
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1,2
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COMMENTS
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Leading 0's in binary expansions are ignored.
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LINKS
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FORMULA
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EXAMPLE
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For n = 11:
- row 11 of A356149 is 1, 2, 3, 4, 5, 11,
- so a(11) = 1 + 2 + 3 + 4 + 5 + 11 = 26.
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PROG
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(PARI) a(n) = { my (b=binary(n)); vecsum(setbinop((i, j) -> my (s=fromdigits(b[i..j], 2)); if (b[i], s, 2^(j-i+1)-1-s), [1..#b])) }
(Python)
def a(n):
N = n.bit_length()
c, s = ((1<<N)-1)^n, set()
for i in range(N):
for l in range(N-i):
mask = ((2<<l)-1) << i
s.add((mask&n) >> i)
s.add((mask&c) >> i)
return sum(s)
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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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