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%I #41 May 30 2024 15:53:15
%S 0,5,7,4,19,104,74,193,515,725,241,1948,2948,709,8746,16451,48443,
%T 47915,61369,41566,136585,710582,476516,1363747,3165833,5491067,
%U 11906702,15854273,6895924,38766838,63676139,3935833,209116033,219826349,265573243,263220940
%N Value of A076042 at its n-th low point.
%H N. J. A. Sloane, <a href="/A324791/b324791.txt">Table of n, a(n) for n = 0..4000</a> (Terms through a(42) from Giovanni Resta)
%H N. J. A. Sloane, <a href="/A324791/a324791_2.txt">Table of n, a(n) for n = 0..10001</a>
%p # Maple program from _N. J. A. Sloane_, Oct 03 2019; guessb = A325056, guessc = A324791 (this sequence).
%p Digits := 64;
%p f := proc(k,M) local j1, twoL, RL, kprime, Mprime;
%p j1 := 3*k^2+7*k+17/4+2*M;
%p if issqr(j1) then lprint("Beware, perfect square: k,M,j1 are ",k,M,j1); fi;
%p twoL := -k-3/2+evalf(sqrt(j1)) ;
%p RL := floor(twoL/2);
%p Mprime := M+(k+1)^2 - (2*k*RL+3*RL+2*RL^2);
%p kprime := 1+k+2*RL;
%p [twol, RL, Mprime, kprime];
%p end;
%p guessb:=[0,5]; b:=5; guessc:=[0,5]; c:=5;
%p for i from 1 to 100 do
%p t1:=f(b,c);
%p b:=t1[4]; c:=t1[3]; guessb:=[op(guessb),b]; guessc:=[op(guessc),c];
%p od:
%p guessb; guessc;
%t a=b=c=d=n=0; L={0}; While[Length[L] < 22, n++; a=b; b=c; c=d; d=c + If[c < n^2, n^2, -n^2]; If[a > b < c < d, AppendTo[L, b]]]; L (* _Giovanni Resta_, Oct 01 2019 *)
%o (PARI) \\ See _Tomas Rokicki_'s PARI program in A076042.
%Y Cf. A076042, A325056, A324792.
%Y If we use primes instead of squares we get A008348, A309226, A324782, A324783.
%K nonn
%O 0,2
%A _N. J. A. Sloane_, Sep 04 2019
%E More terms from _Giovanni Resta_, Oct 01 2019
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