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A003619
Not of form [ e^m ], m >= 1.
(Formerly M2300)
2
1, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53
OFFSET
1,2
COMMENTS
If 1 is excluded (of form [e^0]) then complement of A000149. - Michel Marcus, Jun 16 2013
REFERENCES
J. Roberts, Lure of the Integers, Math. Assoc. America, 1992, p. 11.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
J. Lambek and L. Moser, Inverse and complementary sequences of natural numbers, Amer. Math. Monthly, 61 (1954), 454-458.
FORMULA
a(n) = n + [ log (n + 1 + [ log (n + 1) ]) ].
MATHEMATICA
Table[n + Floor@ Log[n + 1 + Floor@ Log[n + 1]], {n, 50}] (* Michael De Vlieger, Oct 06 2017 *)
PROG
(PARI) a(n) = n + floor( log (n + 1 + floor( log (n + 1) )) ) \\ Michel Marcus, Jun 16 2013
(Haskell)
a003619 n = n + floor (log (x + fromIntegral (floor $ log x)))
where x = fromIntegral n + 1
-- Reinhard Zumkeller, Mar 17 2015
CROSSREFS
Cf. A000195.
Sequence in context: A298420 A197354 A089399 * A377721 A216846 A288674
KEYWORD
nonn
STATUS
approved