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 A248819 Numbers n such that the digits of antisigma(n) end in sigma(n). 0
 79, 479, 2879, 4895, 26879, 79999, 644735, 799999, 2395488, 6399839, 8598719, 63652895, 144726608, 799999999, 935546879, 12640160863, 15282380799, 43687707904, 79999999999 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS All the primes of the form 8*10^k-1 for k>0 are terms (A056721). - Giovanni Resta, May 29 2016 LINKS EXAMPLE sigma(4895) = 6480 and antisigma of 4895 is (4895 * 4896) / 2 - sigma(4895) = 11982960 - 6480 = 11976480. MAPLE with(numtheory): P:=proc(q) local a, n; for n from 1 to q do then a:=ilog10(sigma(n))+1; if sigma(n)=((n*(n+1)/2-sigma(n)) mod 10^a) then print(n); fi; od; end: P(10^9); CROSSREFS Cf. A000230, A024816, A056721. Sequence in context: A142556 A023315 A142618 * A141563 A107954 A098673 Adjacent sequences:  A248816 A248817 A248818 * A248820 A248821 A248822 KEYWORD nonn,more,base AUTHOR Paolo P. Lava, Oct 15 2014 EXTENSIONS a(9)-a(19) from Giovanni Resta, May 29 2016 STATUS approved

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Last modified May 27 18:56 EDT 2020. Contains 334664 sequences. (Running on oeis4.)