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 A291373 a(n) is the smallest number k such that A001065(k) = A002110(n), or 0 if no such k exists. 0
 2, 0, 6, 841, 0, 1722, 30018, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS a(10) = 4057230930. - Giovanni Resta, Aug 23 2017 LINKS FORMULA a(n) = A070015(A002110(n)). - Michel Marcus, Aug 25 2017 EXAMPLE a(5) = 1722 because sigma(1722) - 1722 = 2*3*5*7*11 = A002110(5) and 1722 is the least number with this property. CROSSREFS Cf. A001065, A002110, A070015, A153076, A291356. Sequence in context: A305620 A294470 A283654 * A021487 A197391 A285174 Adjacent sequences:  A291370 A291371 A291372 * A291374 A291375 A291376 KEYWORD nonn,hard,more AUTHOR Altug Alkan, Aug 23 2017 EXTENSIONS a(7) confirmed by Giovanni Resta, Aug 23 2017 STATUS approved

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Last modified August 10 14:50 EDT 2020. Contains 336381 sequences. (Running on oeis4.)