Second align within first align environment with equation numbers

Question

Is it possible to align the for statements here, without dropping the equation numbers? \hfill and && mess up the placement of the equation numbers for me.

Edit:

Picture of what I get after I tried what was posted as answer

Answer 1

Here is a possible solution (if I understand your request correct):

\documentclass{article}

\usepackage{mathtools}

\begin{document}

\begin{alignat}{2}
  \sum_{\mathclap{p \,=\, 1}}^{i}  s_{tp} - \sum_{\mathclap{p \,=\, 2}}^{i+5}                                       m_{tp} &\leq 0 \qquad
  &&\text{for } i = 1, \dots, 39,\\
  \sum_{\mathclap{p \,=\, i}}^{48} f_{tp} - \sum_{\mathclap{\substack{p \,=\, i-5\\ \hphantom{p \,=\,} -2+1}}}^{46} m_{tp} &\geq 0
  &&\text{for } i = 8, \dots, 48,
\end{alignat}

\end{document}

Answer 2

Although a minimal working example (MWE) would really be helpful here, like Steven B. already stated, I think I got you.

Try to use mathtools instead of amsmath. It uses amsmath and extends it more, so you can use the \mathclap command. The lower sum limits of the second summation is causing the gap you dislike:

\documentclass{scrartcl}
\usepackage{mathtools}

\begin{document}
\begin{align}
  \sum_{p=1}^{i}s_{tp} - \sum_{p=2}^{i+5}m_{tp} \leq 0 for i = 1,\cdots,39,\\
  \sum_{p=1}^{48}f_{tp} - \sum_{\mathclap{p=i-5-2+1}}^{46}m_{tp} \geq 0 for i = 8,\cdots,48,
\end{align}
\end{document}