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Records in A249860.
2

%I #8 Sep 20 2016 13:35:36

%S 4,5,7,8,9,20,55,91,187,247,391,475,667,775,1015,1147,1435,1591,1927,

%T 2107,2491,2695,3127,3355,3835,4087,4615,4891,5467,5767,6391,6715,

%U 7387,7735,8455,8827,9595,9991,10807,11227,12091,12535,13447,13915,14875,15367

%N Records in A249860.

%C The indices corresponding to the records are in A276706.

%F Conjectures: (Start)

%F a(n) = (347+27*(-1)^n)/2 - 3*(27+(-1)^n)*n + 9*n^2 for n>6.

%F a(n) = a(n-1)+2*a(n-2)-2*a(n-3)-a(n-4)+a(n-5) for n>11.

%F G.f.: x*(4+x-6*x^2-x^3+x^4+10*x^5+35*x^6+15*x^7+27*x^8-x^9-13*x^10) / ((1-x)^3*(1+x)^2).

%F (End)

%o (PARI) lista(nn) = {rec = 0; for (n=1, nn, an = lcm(n-3, n+3); if (an > rec, rec = an; print1(rec, ", ")););} \\ _Michel Marcus_, Sep 16 2016

%Y Cf. A249860, A276704, A276706.

%K nonn

%O 1,1

%A _Colin Barker_, Sep 15 2016