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Indices of records in A249860.
1

%I #8 Sep 20 2016 13:35:56

%S 1,2,4,5,6,7,8,10,14,16,20,22,26,28,32,34,38,40,44,46,50,52,56,58,62,

%T 64,68,70,74,76,80,82,86,88,92,94,98,100,104,106,110,112,116,118,122,

%U 124,128,130,134,136,140,142,146,148,152,154,158,160,164,166

%N Indices of records in A249860.

%C The records corresponding to the indices are in A276705.

%F Conjectures: (Start)

%F a(n) = a(n-1)+a(n-2)-a(n-3) for n>3.

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

%F G.f.: x*(1+x+x^2-x^4+x^7+3*x^8) / ((1-x)^2*(1+x)).

%F (End)

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

%Y Cf. A249860, A276705.

%K nonn

%O 1,2

%A _Colin Barker_, Sep 15 2016