pdsolve2(y(n_,t)=a_,y_) := if(hasnot(a,t), dsolve(a-1,y)+t^n/n!, pdsolve(y(n,t)+expand(-(a)),y)); #dsolve(y(n_,t)=a_,y_) := if(hasnot(a,y), if(hasnot(a,t), dsolve(a-1,y)+t^n/n!, if(hasnot(a,x), dsolve(toy(a),y,t,n), dsolve(y(n,t)-(a),y) ) ), if(hasnot(a,t),if(hasnot(a-y,y), dsolve(a,y)+C_3*exp(t),dsolve(a,y)), dsolve(y(n,t)-(a),y) )); #dsolve(y(p_,t)=y(q_,x_)+d_,y_):= if(hasnot(d,y),if(hasnot(a,t), dsolve(1-d,y,x,q)+t^p/p!, if(has(d,t), if(has(d,x), psolution(0,-d,p,x,q), int(d,t,p) ),-int(d,x,q) )), if(hasnot(a,t), dsolve(-d,y,x,q),dsolve(y(p,t)-y(q,x)-d,y) )); #dsolve(y(p_,t)=a_*y(q_,x_)+d_,y_):= if(isconstant(a) and hasnot(d,y), C_1+C_2*(a*t^p/p!+x^q/q!)+if(has(d,t),if(has(d,x), psolution(a,-d,p,x,q), int(d,t,p) ), -int(d/a,x,q) )); #dsolve(y(p_,t)=y(q_,x_),y_):= C_1+C_2*(t^p/p!+x^q/q!)+if(q>=2,C_3*x,0); #dsolve(y(p_,t)=a_*y(q_,x_),y_):= if(isconstant(a), C_1+C_2*(t^p/p!+x^q/q!/a)+if(q>=2,C_3*x,0), if(hasnot(a,y), int(1/a,x,q)+t^p/p!+C_1, dsolve(y(p,t)-a*y(q,x),y) )); pdsolve2(a_):=pdsolve2(replace(toy(a),y(x),y),y);