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 A236355 Terms of A050973 that give maximum record values for A050973(k)/A050972(k). 1
 28, 224, 234, 496, 6200, 8128, 174592, 544635, 2886100, 33550336 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The corresponding terms in A050972 are: 6, 40, 12, 6, 30, 6, 40, 6, ... Note the subsequence 28, 496, 8128, 33550336: friends of 6 (cf A000396). LINKS Eric Weisstein's World of Mathematics, Friendly Pair. EXAMPLE 28/6 < 224/40 < 234/12 < 496/6 < 6200/30 < 8128/6 < 174592/40 < .... PROG (PARI) isrmax(i, rmax) = {si = sigma(i); if (gcd(si, i) == 1, return (0)); s = si/i; for (j=1, i\rmax, if ((sigma(j)/j) == s, if ((newr = i/j) > rmax, return (newr)); ); ); return (0); } lista(nn) = {rmax = 1; for (i = 1, nn, if ((newr = isrmax(i, rmax)), rmax = newr; print1(i, ", "); ); ); } CROSSREFS Cf. A050972, A050973, A236372. Sequence in context: A249710 A269621 A269437 * A133071 A339137 A135180 Adjacent sequences:  A236352 A236353 A236354 * A236356 A236357 A236358 KEYWORD nonn,more AUTHOR Michel Marcus, Jan 23 2014 STATUS approved

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Last modified September 24 09:10 EDT 2021. Contains 347630 sequences. (Running on oeis4.)