Answers

2014-04-15T12:07:34+05:30
Clearly,if n is div. by 5,then n+5 or n-5 willbe so
for n+8,n+13 or n+3
for n+12,n+17 or n+7
for n+4,n+9 or n-1
for n+16,n+21 or n+11
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