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A084293
a(n) = 2n + A054905(n).
2
436, 305635361, 110, 35, 195566, 77, 26, 55, 38, 76, 938, 104, 212308, 85, 74, 106677, 86, 161
OFFSET
1,1
COMMENTS
The sequence begins 436, 305635361, 110, 35, 195566, 77, 26, 55, 38, 76, 938, 104, 212308, 85, 74, 106677, 86, 161, ?, 91, 87, 92, 122, 111, 1585396, 145, 94, 76627, 10283, 159, 772, 133, 122, 412, 194, 142, 964, 205, 374, 925, 6725, 209, ?, 1015, 178, ?, ?, 206, 146, ?, ..., where the other missing terms (designated by "?") are unknown, if they exist (see also A206768).
FORMULA
Composite x satisfying sigma(x-2n) = sigma(x) - 2n.
EXAMPLE
To terms of A054905, where sigma(x+2n)=sigma(x)+2n replacing x+2n=y,x=y-2n, we get sigma(y)-2n=sigma(y-2n);
For several analogous sequences, the corresponding "mirror-solutions" can be easily constructed. See: e.g. A015913-A015918; A050507, A054799, A054903-A054906; A054982-A054987; A059118; A055009, A055458, A063500, etc.
CROSSREFS
Cf. A054905.
Sequence in context: A243233 A216988 A190828 * A237939 A088893 A043447
KEYWORD
nonn,more
AUTHOR
Labos Elemer, May 26 2003
STATUS
approved