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%I #14 Oct 16 2020 08:47:08
%S 1,2,6,12,16,30,42,54,66,78,105,120,156,330,525,546,831,1071,1251,
%T 1386,1875,1890,2136,2241,2331,2541,2565,2736,2871,3165,3606,3885,
%U 4710,5106,5220,5505,6375,6390,6426,6615,6786,8310,8571,9066,10050,10176,10221,10611,11865,11955,12096
%N Record values in A243145.
%p f:= proc(n) local k;
%p for k from (n mod 2)+1 by 2 do
%p if isprime(n+k) and isprime(n+k^2) then return k fi
%p od
%p end proc:
%p f(1):= 1:
%p vmax:= 0: recvals:= NULL:
%p for n from 1 to 10^7 do
%p v:= f(n);
%p if v > vmax then
%p vmax:= v; recvals:= recvals, v;
%p fi
%p od:
%p recvals;
%t f[n_] := Module[{k}, For[k = Mod[n, 2]+1, True, k += 2, If[PrimeQ[n + k] && PrimeQ[n + k^2], Return [k]]]]; f[1] = 1;
%t vmax = 0;
%t Reap[For[n = 1, n <= 10^6, n++, v = f[n]; If[v > vmax, vmax = v; Print["n = ", n, " v = ", v]; Sow[v]]]][[2, 1]] (* _Jean-François Alcover_, Oct 16 2020, after Maple *)
%Y Cf. A243145, A299073.
%K nonn,more
%O 1,2
%A _Robert Israel_, Feb 02 2018
%E a(34)-a(51) from _Chai Wah Wu_, Sep 10 2019
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