Reciprocal of 61

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Theorem

The decimal expansion of the reciprocal of $61$ is as follows:

$\dfrac 1 {61} = 0 \cdotp \dot 01639 \, 34426 \, 22950 \, 81967 \, 21311 \, 47540 \, 98360 \, 65573 \, 77049 \, 18032 \, 78688 \, 5245 \dot 9$

This sequence is A021065 in the On-Line Encyclopedia of Integer Sequences (N. J. A. Sloane (Ed.), 2008).


Proof

Performing the calculation using long division:

   0.01639344262295081967213114754098360655737704918032786885245901...
  --------------------------------------------------------------------
61)1.00000000000000000000000000000000000000000000000000000000000000000
     61    122      61     61     488     183      183    305        
     --    ---     ---     --     ---     ---      ---    ---
     390    380     590     90     220     470      170    150
     366    366     549     61     183     427      122    122
     ---    ---     ---     --     ---     ---      ---    ---
      240    140     410    290     370     430      480    280
      183    122     366    244     366     427      427    244
      ---    ---     ---    ---     ---     ---      ---    ---
       570    180     440    460      400     300     530    360
       549    122     427    427      366     244     488    305
       ---    ---     ---    ---      ---     ---     ---    ---
        210    580     130    330      340     560     420    550
        183    549     122    305      305     549     366    549
        ---    ---     ---    ---      ---     ---     ---    ---
         270    310      80    250      350     110     540     100
         244    305      61    244      305      61     488      61
         ---    ---      --    ---      ---     ---     ---     ---
          260     500    190     600     450     490     520    ...
          244     488    183     549     427     488     488
           --     ---    ---     ---     ---     ---     ---
           160     120     70     510     230      200    320
           122      61     61     488     183      183    305
           ---     ---     --     ---     ---      ---    ---

$\blacksquare$