SPECIAL NUMBERS AND SEQUENCES
! | This post is a part of the Special Questions Directory focusing on Quant topics traditionally neglected and not covered by conventional sources but still tested on the GMAT. Many of these are above average difficulty questions |
Questions about special numbers and sequences. Note that you do NOT need to know or study these numbers or sequences in advance, the questions themselves will contain their definition. If you encounter such kind of questions, read the definition carefully and don't be confused by weird numbers/sequences described there.
A square-free integer: a-positive-integer-is-called-square-free-if-it-has-no-fact-159462.html
A Sophie Germain prime: a-sophie-germain-prime-is-any-positive-prime-number-p-for-132650.html
A Farey sequence: a-farey-sequence-of-order-n-is-the-sequence-of-fractions-129825.html
A coprime sequence: an-infi-nite-sequence-of-positive-integers-is-called-a-127496.html
A perfect sequence: an-infinite-sequence-of-positive-integers-is-called-a-127696.html
Twin primes: twin-primes-are-defined-as-prime-numbers-that-can-be-express-128433.html
Length of an integer:
for-any-positive-integer-n-n-1-the-length-of-n-is-the-126368.html
for-any-integer-k-1-the-term-length-of-an-integer-108124.html
for-any-positive-integer-n-the-length-of-n-is-defined-as-126740.html
Rhyming primes:
two-different-primes-may-be-said-to-rhyme-128903.html
two-different-primes-may-be-said-to-rhyme-around-an-integer-107290.html
The connection between integers: the-connection-between-any-two-positive-integers-a-and-b-128360.html
Sexy primes: a-pair-of-prime-numbers-that-can-be-expressed-in-the-form-p-174141.html
Alpha sequence: an-infinite-sequence-of-positive-integers-is-called-an-alph-55723.html
Beta sequence: an-infinite-sequence-of-positive-integers-is-called-a-beta-151947.html
A repunit number: a-repunit-is-a-positive-integer-that-contains-only-the-digit-174819.html#p1385302