ፋክቶሪያል
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{|class="wikitable" style="margin:0; text-align: right;" cellspacing="0"
! ቀ
! ቀ! (የ ቀ ፋክቶሪያል)
|-
| 0 || 1
|-
| 1 || 1
|-
| 2 || 2
|-
| 3 || 6
|-
| 4 || 24
|-
| 5 || 120
|-
| 6 || 720
|-
| 7 || 5,040
|-
| 8 || 40,320
|-
| 9 || 362,880
|-
| 10 || 3,628,800
|-
| 15 || 1,307,674,368,000
|-
| 20 || 2,432,902,008,176,640,000
|-
| 25 || 1.5511210043 × 10<sup>25</sup>
|-
| 50 || 3.0414093202 × 10<sup>64</sup>
|-
| 70 || 1.1978571670 × [[googol|10<sup>100</sup>]]
|-
| 100 || 9.3326215444 × 10<sup>157</sup>
|-
| 171 || [[Double precision floating-point format#Double precision examples|1.2410180702 × 10<sup>309</sup>]]
|-
| 450 || 1.7333687331 × 10<sup>1,000</sup>
|-
| 1,000 || 4.0238726008 × 10<sup>2,567</sup>
|-
| 3,249 || 6.4123376883 × 10<sup>10,000</sup>
|-
| 10,000 || 2.8462596809 × 10<sup>35659</sup>
|-
| 25,206 || 1.2057034382 × 10<sup>100,000</sup>
|-
| 100,000 || 2.8242294080 × 10<sup>456,573</sup>
|-
| 205,023 || 2.5038989317 × 10<sup>1,000,004</sup>
|-
| 1,000,000 || 8.2639316883 × 10<sup>5,565,708</sup>
|-
| 1.0248383838 × 10<sup>98</sup> || [[googolplex|10<sup>1.0000000000 × 10<sup>100</sup></sup>]]
|-
| 1.0000000000 × [[googol|10<sup>100</sup>]] || 10<sup>9.9565705518 × 10<sup>101</sup></sup>
|-
| [[Double precision floating-point format#Double precision examples|1.7976931349 × 10<sup>308</sup>]] || 10<sup>5.5336665775 × 10<sup>310</sup></sup>
|}

</div></div>

'''ፋክቶሪያል''' በሂሳብ፣ ያንድ ሙሉ [[ቁጥር]]፣ ለምሳሌ «ቀ» ([[ፖዘቲቭ]]) ፋክቶሪአል ማለት በ «ቀ!» ሲመሰል፣ ትርጉሙም የተሰጠን ቁጥርና ከሱ በታች ያሉ ድርድር ቁጥሮች (እስከ 1) ተባዝተው የሚሰጡት ውጤት ማለት ነው።

ቀ! = ቀ*(ቀ-1)! = ቀ*(ቀ-1)*(ቀ-2)!  =..... = ቀ.(ቀ-1).(ቀ-2).(ቀ-3).(ቀ-4).(ቀ-5) .....(3).(2).(1) 

ለምሳሌ፦
:<math>5 ! = 1  \times  2  \times  3  \times  4  \times  5 = 120  \ </math>

የዜሮ ፋክቶሪያል ለየት ያለ ትርጉም ሲኖርው ውጤቱም 1 ነው ተብሎ በስምምነት ተተርጉሟል።

{{መዋቅር}}

[[መደብ:ሥነ ቁጥር]]
ቀ ቀ! (የ ቀ ፋክቶሪያል) 0  1 1  1 2  2 3  6 4  24 5  120 6  720 7  5,040 8  40,320 9  362,880 10  3,628,800 15  1,307,674,368,000 20  2,432,902,008,176,640,000 25  1.5511210043 × 1025 50  3.0414093202 × 1064 70  1.1978571670 × 10100 100  9.3326215444 × 10157 171  1.2410180702 × 10309 450  1.7333687331 × 101,000 1,000  4.0238726008 × 102,567 3,249  6.4123376883 × 1010,000 10,000  2.8462596809 × 1035659 25,206  1.2057034382 × 10100,000 100,000  2.8242294080 × 10456,573 205,023  2.5038989317 × 101,000,004 1,000,000  8.2639316883 × 105,565,708 1.0248383838 × 1098  101.0000000000 × 10100 1.0000000000 × 10100  109.9565705518 × 10101 1.7976931349 × 10308  105.5336665775 × 10310

ፋክቶሪያል በሂሳብ፣ ያንድ ሙሉ ቁጥር፣ ለምሳሌ «ቀ» (ፖዘቲቭ) ፋክቶሪአል ማለት በ «ቀ!» ሲመሰል፣ ትርጉሙም የተሰጠን ቁጥርና ከሱ በታች ያሉ ድርድር ቁጥሮች (እስከ 1) ተባዝተው የሚሰጡት ውጤት ማለት ነው።

ቀ! = ቀ*(ቀ-1)! = ቀ*(ቀ-1)*(ቀ-2)!  =..... = ቀ.(ቀ-1).(ቀ-2).(ቀ-3).(ቀ-4).(ቀ-5) .....(3).(2).(1) 

ለምሳሌ፦

የዜሮ ፋክቶሪያል ለየት ያለ ትርጉም ሲኖርው ውጤቱም 1 ነው ተብሎ በስምምነት ተተርጉሟል።

መደብ:ሥነ ቁጥር