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Category: Number Theory

Prove-that-for-p-q-r-N-lcm-p-q-r-gcd-p-q-r-p-q-r-gcd-p-q-gcd-q-r-gcd-r-p-

Question Number 66275 by Rasheed.Sindhi last updated on 12/Aug/19 $${Prove}\:{that}\:{for}\:{p},{q},{r}\in\mathbb{N} \\ $$$$\frac{\mathrm{lcm}\left({p},{q},{r}\right)}{\mathrm{gcd}\left({p},{q},{r}\right)}=\frac{{p}×{q}×{r}}{\mathrm{gcd}\left({p},{q}\right)×\mathrm{gcd}\left({q},{r}\right)×\mathrm{gcd}\left({r},{p}\right)} \\ $$ Commented by Prithwish sen last updated on 12/Aug/19 $$\mathrm{p}=\mathrm{nn}_{\mathrm{1}} \mathrm{n}_{\mathrm{2}} \mathrm{x},\mathrm{q}=\mathrm{nn}_{\mathrm{2}}…

Prove-by-induction-on-n-for-n-2-u-n-2-3-n-1-for-the-sequence-u-n-defined-by-the-recurrence-relation-u-1-1-

Question Number 591 by 112358 last updated on 04/Feb/15 $${Prove}\:{by}\:{induction}\:{on}\:{n},\:{for}\:{n}\geqslant\mathrm{2}, \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:{u}_{{n}} \:\geqslant\:\mathrm{2}^{\mathrm{3}^{{n}−\mathrm{1}} } \\ $$$${for}\:{the}\:{sequence}\:\left\{{u}_{{n}} \right\}\:{defined}\:{by}\: \\ $$$${the}\:{recurrence}\:{relation} \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:{u}_{\mathrm{1}} =\mathrm{1}\: \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:{u}_{{n}+\mathrm{1}} =\left({u}_{{n}}…

Give-the-result-of-the-following-computation-as-an-integer-in-the-usual-decimal-form-303-000-000-000-303-3-300-000-033-1-000-100-010-001-

Question Number 518 by Yugi last updated on 25/Jan/15 $${Give}\:{the}\:{result}\:{of}\:{the}\:{following}\:{computation}\:{as}\:{an}\:{integer}\:{in}\:{the}\:{usual}\:{decimal} \\ $$$${form}.\: \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\frac{\mathrm{303},\mathrm{000},\mathrm{000},\mathrm{000},\mathrm{303}×\mathrm{3},\mathrm{300},\mathrm{000},\mathrm{033}}{\mathrm{1},\mathrm{000},\mathrm{100},\mathrm{010},\mathrm{001}} \\ $$ Answered by prakash jain last updated on 22/Jan/15 $$\frac{\mathrm{303}\left(\mathrm{10}^{\mathrm{12}}…