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 A182142 Abundance d=sigma(N)-2*N=A033880(N) of numbers N=A181595(n) (which have d>0 as divisor). 1
 4, 3, 2, 12, 10, 8, 4, 2, 120, 7, 56, 78, 8, 2, 2, 672, 32, 16, 4, 2, 532, 152, 136, 8, 68, 31, 992, 128, 8, 64, 32, 16, 4, 8, 128, 32, 8, 2, 43648, 2528, 32, 4, 2, 523776, 32, 2272, 32, 32 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS It is conjectured that only powers of 2 can occur more than once. LINKS FORMULA A182142 = A033880 o A181595. PROG (PARI) f182142(n)={my(d=sigma(n)-2*n); d>0 & !(n%d) & return(d)} /* NB: This is neither A182142 nor is_A182142, it is actually A033880(n)*is_A181595(n) */ for(n=1, 1e6, (t=f182142(n))&print1(t", ")) CROSSREFS Sequence in context: A033882 A062111 A181596 * A033881 A099406 A202696 Adjacent sequences:  A182139 A182140 A182141 * A182143 A182144 A182145 KEYWORD nonn AUTHOR M. F. Hasler, Apr 14 2012 STATUS approved

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