A301646 - OEIS

%I #8 Apr 15 2018 14:16:36

%S 1,2,4,6,10,12,14,18,24,30,42,54,60,66,70,78,84,90,114,120,126,150,

%T 168,180,210,270,294,300,330,390,420,462,510,546,570,630,660,714,770,

%U 780,840,924,990,1050,1170,1260,1320,1386,1470,1560,1638

%N Numbers k at which A062776(k) reaches a record high.

%e A062776(6) = 576, larger than any A062776(k) for 1 <= k < 6 so 6 is in the sequence.

%t With[{s = Table[GCD[(n + 2)!, n^n], {n, 1700}]}, Map[FirstPosition[s, #][[1]] &, Union@ FoldList[Max, s]]] (* _Michael De Vlieger_, Mar 26 2018 *)

%o (PARI) val(n, p) = my(r=0); while(n, r+=n\=p); r

%o A062776(n) = my(f = factor(n)[, 1]~); prod(i=1, #f, f[i] ^ min(n, val(n + 2, f[i])))

%o upto(n) = my(r = 0, res = List(), c); for(i = 1, n, c = A062776(i); if(c > r, r = c; listput(res, i))); res

%Y Cf. A062776.

%K nonn,easy

%O 1,2

%A _David A. Corneth_, Mar 25 2018