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A372591
Numbers whose binary weight (A000120) plus bigomega (A001222) is even.
10
2, 6, 7, 8, 9, 10, 11, 13, 15, 19, 24, 28, 31, 32, 33, 34, 36, 37, 39, 40, 41, 42, 44, 46, 47, 50, 51, 52, 54, 57, 58, 59, 60, 61, 65, 67, 70, 73, 76, 77, 79, 85, 86, 90, 95, 96, 97, 98, 103, 106, 107, 109, 110, 111, 112, 117, 119, 123, 124, 126, 127, 128, 129
OFFSET
1,1
COMMENTS
The odd version is A372590.
EXAMPLE
The terms (center), their binary indices (left), and their weakly decreasing prime indices (right) begin:
{2} 2 (1)
{2,3} 6 (2,1)
{1,2,3} 7 (4)
{4} 8 (1,1,1)
{1,4} 9 (2,2)
{2,4} 10 (3,1)
{1,2,4} 11 (5)
{1,3,4} 13 (6)
{1,2,3,4} 15 (3,2)
{1,2,5} 19 (8)
{4,5} 24 (2,1,1,1)
{3,4,5} 28 (4,1,1)
{1,2,3,4,5} 31 (11)
{6} 32 (1,1,1,1,1)
{1,6} 33 (5,2)
{2,6} 34 (7,1)
{3,6} 36 (2,2,1,1)
{1,3,6} 37 (12)
{1,2,3,6} 39 (6,2)
{4,6} 40 (3,1,1,1)
{1,4,6} 41 (13)
{2,4,6} 42 (4,2,1)
MATHEMATICA
Select[Range[100], EvenQ[DigitCount[#, 2, 1]+PrimeOmega[#]]&]
CROSSREFS
For sum (A372428, zeros A372427) we have A372587, complement A372586.
For minimum (A372437) we have A372440, complement A372439.
Positions of even terms in A372441, zeros A071814.
For maximum (A372442, zeros A372436) we have A372589, complement A372588.
The complement is A372590.
For just binary indices:
- length: A001969, complement A000069
- sum: A158704, complement A158705
- minimum: A036554, complement A003159
- maximum: A053754, complement A053738
For just prime indices:
- length: A026424 A028260 (count A027187), complement (count A027193)
- sum: A300061 (count A058696), complement A300063 (count A058695)
- minimum: A340933 (count A026805), complement A340932 (count A026804)
- maximum: A244990 (count A027187), complement A244991 (count A027193)
A019565 gives Heinz number of binary indices, adjoint A048675.
A029837 gives greatest binary index, least A001511.
A031215 lists even-indexed primes, odd A031368.
A048793 lists binary indices, length A000120, reverse A272020, sum A029931.
A070939 gives length of binary expansion.
A112798 lists prime indices, length A001222, reverse A296150, sum A056239.
Sequence in context: A096909 A073005 A091942 * A047555 A184939 A043050
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 14 2024
STATUS
approved