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A190151
A190149 converted to base 10 and halved.
2
9, 17, 19, 25, 33, 34, 35, 37, 39, 41, 49, 51, 57, 65, 66, 67, 69, 70, 71, 73, 75, 77, 79, 81, 83, 89, 97, 98, 99, 101, 103, 105, 113, 115, 121, 129, 130, 131, 132, 133, 134, 135, 137, 138, 139, 141, 142, 143, 145, 147, 149, 151, 153, 155, 157, 159, 161, 162, 163, 165, 167, 169, 177, 179, 185, 193, 194, 195, 197, 198, 199, 201, 203, 205, 207, 209, 211
OFFSET
1,1
COMMENTS
Take the even numbers n such that in base 2 lunar arithmetic, the sum of the divisors of n is not of the form 2^k-1, and divide them (in ordinary arithmetic) by 2 (cf. A190149, A190150)
LINKS
D. Applegate, M. LeBrun and N. J. A. Sloane, Dismal Arithmetic [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing]
D. Applegate, M. LeBrun, N. J. A. Sloane, Dismal Arithmetic, J. Int. Seq. 14 (2011) # 11.9.8.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, May 05 2011
STATUS
approved