This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
calcPyr:=proc(i, j, k, l) option remember; if (l<0) then 0 elif (i*j*k>l) then 0 elif k=1 then if (i*j=l) then 1 else 0; fi; else s:=0; a:=0; b:=0; while ((i+a)*j*(k-1)<=l-i*j) do b:=0; while ((i+a)*(j+b)*(k-1)<=l-i*j) do s:=s+(a+1)*(b+1)*calcPyr(i+a, j+b, k-1, l-i*j); b:=b+1; od; a:=a+1; od; s; fi; end; countPyr:=proc(l) s:=0; for k to l do i:=1: while (i*k<=l) do j:=1; while (i*k*j<=l) do s:=s+t^k*calcRecPyr(i, j, k, l); j:=j+1; od: i:=i+1; od; od; s; end; enum=[seq(countPyr(ii), ii=1..200)]; serie_quasiPyr:=proc(l) global enum;local ii; map(coeff,enump,t^l); select(x->x>0,%); sum(t^(ii-1)*%[ii],ii=1..nops(%)); end; serie_quasiPyr(100): [1,seq(coeff(%,t^ii)-1,ii=1..50)];
calc2can:=proc(i, j, k, l) option remember;
if (l<0) then 0
elif (i*j*k>l) then 0
elif k=1 then if (i*j=l) then 1 else 0; fi;
else s:=0; a:=0; b:=0;
while ((i+a)*j*(k-1)<=l-i*j) do
b:=0;
while ((i+a)*(j+b)*(k-1)<=l-i*j) do
s:=s+binomial(i+a, a)*binomial(j+b, b)*calc2can(i+a, j+b, k-1, l-i*j);
b:=b+1;
od;
a:=a+1;
od;
s;
fi;
end;
comptec:=proc(l)
s:=0;
for k to l do
i:=1:
while (i*k<=l) do
j:=1;
while (i*k*j<=l) do
s:=s+t^k*calc2can(i, j, k, l);
j:=j+1;
od:
i:=i+1;
od;
od;
s;
end;
enumc:=[seq(comptec(ii), ii=1..485)]:
convert([seq(enumc[i]*x^i, i=1..nops(%))], `+`):seriec:=subs(t=1, %);
calc2can[i_, j_, k_, l_] := calc2can[i, j, k, l] = Module[{}, Which[l < 0, 0, i*j*k > l, 0, k == 1, If [i*j == l, 1, 0], True, s = 0; a = 0; b = 0;
While[(i + a)*j*(k - 1) <= l - i*j, b = 0; While[(i + a)*(j + b)*(k - 1) <= l - i*j, s = s + Binomial[i + a, a]*Binomial[j + b, b]*calc2can[i + a, j + b, k - 1, l - i*j]; b++]; a++]; s]];
comptec[l_] := Module[{s = 0}, For[k = 1, k <= l, k++, i = 1; While[i*k <= l, j = 1; While[i*k*j <= l, s = s + t^k*calc2can[i, j, k, l]; j++]; i++] ]; s ];
Array[comptec, 40] /. t -> 1 (* Jean-François Alcover, Dec 05 2017, translated from Maple *)
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