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 A214547 Deficient numbers for which the (absolute value of) abundance is not a divisor. 1
 3, 5, 7, 9, 11, 13, 14, 15, 17, 19, 21, 22, 23, 25, 26, 27, 29, 31, 33, 34, 35, 37, 38, 39, 41, 43, 45, 46, 47, 49, 50, 51, 52, 53, 55, 57, 58, 59, 61, 62, 63, 65, 67, 68, 69, 71, 73, 74, 75, 76, 77, 79, 81, 82, 83, 85, 86, 87, 89, 91, 92, 93, 94, 95, 97, 98, 99, 101, 103, 105, 106 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This is to A214408 as deficient numbers are to abundant numbers. Differs from A097218, which does not contain 105, for example. The deficient numbers which are *not* in the sequence are 2, 4, 8, 10, 16, 32, 44, 64, 128, 136, 152, 184, 256, 512, 752, 884, 1024, 2048, 2144, 2272, 2528, 4096, 8192, 8384, 12224, 16384, 17176, 18632, 18904, 32768, 32896, 33664, ... the union of powers of 2 and the terms of A060326. - M. F. Hasler, Jul 21 2012 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 FORMULA Terms A005100(n) such that |A033880(A005100(n))| does not divide A005100(n). EXAMPLE 7 is in the sequence because 7 is deficient, and its abundance is -6, and |-6| = 6 does not divide 7. MAPLE filter:= proc(n) local t; t:= 2*n-numtheory:-sigma(n); t > 0 and n mod t <> 0 end proc: select(filter, [\$1..200]); # Robert Israel, Nov 13 2019 PROG (PARI) is_A214547(n)={sigma(n)<2*n & n%(2*n-sigma(n))} \\ M. F. Hasler, Jul 21 2012 CROSSREFS Cf. A005100, A033880, A214408. Sequence in context: A329405 A194391 A081534 * A097218 A196546 A231773 Adjacent sequences:  A214544 A214545 A214546 * A214548 A214549 A214550 KEYWORD nonn,easy AUTHOR Jonathan Vos Post, Jul 20 2012 EXTENSIONS Given terms double-checked with the PARI script by M. F. Hasler, Jul 21 2012 STATUS approved

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Last modified September 29 09:40 EDT 2020. Contains 337428 sequences. (Running on oeis4.)