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 A036434 Integers which cannot be written as k+tau(k) for some k. 2
 1, 3, 6, 8, 11, 16, 17, 20, 22, 23, 27, 29, 35, 36, 40, 41, 44, 46, 47, 53, 54, 57, 60, 65, 67, 68, 70, 76, 77, 79, 80, 83, 87, 88, 92, 93, 94, 100, 101, 106, 107, 114, 116, 117, 121, 125, 128, 131, 132, 134, 135, 140, 142, 148, 155, 156, 157, 158, 161, 164, 166 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Invented by the HR concept formation program. LINKS S. Colton, Refactorable Numbers - A Machine Invention, J. Integer Sequences, Vol. 2, 1999, #2. EXAMPLE None of 1,2,3,4,5,6,7 are such that k+tau(k)=8, so 8 is in the sequence. PROG (PARI) isok(n) = sum(k=1, n, k+numdiv(k) != n) == n; \\ Michel Marcus, Dec 08 2014 CROSSREFS Cf. A036438. Sequence in context: A164910 A276583 A135736 * A298795 A140400 A190430 Adjacent sequences:  A036431 A036432 A036433 * A036435 A036436 A036437 KEYWORD nonn AUTHOR Simon Colton (simonco(AT)cs.york.ac.uk) STATUS approved

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Last modified May 19 17:48 EDT 2019. Contains 323395 sequences. (Running on oeis4.)