November 1st, 2019, 10:52 PM |
#21 |

Senior Member Joined: Aug 2018 From: România Posts: 110 Thanks: 7 |
Hello all, From the "WolframAlpha" read: https://www.wolframalpha.com/input/?...E2%3Dn%5E2%2B1. What do you think about this shocking result! All the best, Integrator |

November 2nd, 2019, 01:20 AM |
#22 | |

Global Moderator Joined: Dec 2006 Posts: 21,107 Thanks: 2324 | Quote:
For $n \leqslant 1$, $\displaystyle \sum_{k=n}^{k=1} k = -\frac12(n - 2)(n + 1)$. $\displaystyle \frac12n(n + 1) - \frac12(n - 2)(n + 1) = n + 1$ | |

November 2nd, 2019, 07:38 AM |
#23 | |

Senior Member Joined: Aug 2018 From: România Posts: 110 Thanks: 7 | Quote:
I do not understand!From the "WolframAlpha" read for $\displaystyle n>0$: https://www.wolframalpha.com/input/?...k%3Dn%29%5E1+k. How can you explain this result given by "WolframAlpha"?!?! ---------------------------------------------------------------------- And about https://www.wolframalpha.com/input/?...n%29%5E1+k%5E2 and https://www.wolframalpha.com/input/?...E2%3Dn%5E2%2B1 , what can you say?Thank you very much! All the best, Integrator
Last edited by Integrator; November 2nd, 2019 at 07:51 AM.
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