- prime.rb

Internal use. An implementation of eratosthenesâ€™s sieve

next_to(n)
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returns the least odd prime number which is greater than `n`

.

# File prime.rb, line 441 def next_to(n) n = (n-1).div(2)*2+3 # the next odd number to given n table_index, integer_index, bit_index = indices(n) loop do extend_table until @tables.length > table_index for j in integer_index...ENTRIES_PER_TABLE if !@tables[table_index][j].zero? for k in bit_index...BITS_PER_ENTRY return NUMS_PER_TABLE*table_index + NUMS_PER_ENTRY*j + 2*k+1 if !@tables[table_index][j][k].zero? end end bit_index = 0 end table_index += 1; integer_index = 0 end end

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