A236355 Terms of A050973 that give maximum record values for A050973(k)/A050972(k).
28, 224, 234, 496, 6200, 8128, 174592, 544635, 2886100, 33550336
Offset: 1
Examples
28/6 < 224/40 < 234/12 < 496/6 < 6200/30 < 8128/6 < 174592/40 < ....
Links
- Eric Weisstein's World of Mathematics, Friendly Pair.
Programs
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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, ", ");););}
Comments