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 A036432 Sets a record for the number of positive integers which, when added to the number of their divisors, gives n. 1
 1, 2, 7, 38, 122, 2766, 64686, 1972296, 5387768, 56208248, 753815160, 130065181784 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Invented by the HR concept formation program. LINKS S. Colton, Refactorable Numbers - A Machine Invention, J. Integer Sequences, Vol. 2, 1999, #2. FORMULA Sets record for |{b in N : b + tau(b) = n}|. EXAMPLE 1 [ first with 0 ]. 2=1+tau(1) [ first with 1 ]. 7=4+tau(4) and 5+tau(5) [ first with 2 ]. 38=30+tau(30) and 32+tau(32) and 34+tau(34) [ first with 3 ]. PROG (PARI) nbi(n) = {nb = 0; for (i = 1, n, if ((i + numdiv(i)) == n, nb++); ); nb; } lista(nn) = {rec = -1; for (n = 1, nn, new = nbi(n); if (new > rec, print1(n, ", "); rec = new; ); ); } \\ Michel Marcus, Aug 31 2013 CROSSREFS Cf. A036431. Sequence in context: A182331 A173762 A180269 * A275621 A094431 A256032 Adjacent sequences:  A036429 A036430 A036431 * A036433 A036434 A036435 KEYWORD hard,nonn,nice,more AUTHOR Simon Colton (simonco(AT)cs.york.ac.uk) EXTENSIONS More terms from Julian Richardson (julianr(AT)dai.ed.ac.uk), who has searched up to 100000000. a(10)-a(11) from Donovan Johnson, Feb 19 2009 STATUS approved

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Last modified May 21 18:43 EDT 2019. Contains 323444 sequences. (Running on oeis4.)