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277 (read as two hundred and seventy-seven) is the natural number following 276 and preceding 278. ==Mathematical properties== 277 is the 59th prime number, and is a regular prime. It is the smallest prime ''p'' such that the sum of the inverses of the primes up to ''p'' is greater than two. Since 59 is itself prime, 277 is a super-prime. 59 is also a super-prime (it is the 17th prime), as is 17 (the 7th prime). However, 7 is the fourth prime number, and 4 is not prime. Thus, 277 is a super-super-super-prime but not a super-super-super-super-prime.〔.〕 It is the largest prime factor of the Euclid number 510511 = 2 × 3 × 5 × 7 × 11 × 13 × 17 + 1. As a member of the lazy caterer's sequence, 277 counts the maximum number of pieces obtained by slicing a pancake with 23 straight cuts. 277 is also a Perrin number, and as such counts the number of maximal independent sets in an icosagon.〔.〕 There are 277 ways to tile a 3 × 8 rectangle with integer-sided squares, and 277 degree-7 monic polynomials with integer coefficients and all roots in the unit disk. On an infinite chessboard, there are 277 squares that a knight can reach from a given starting position in exactly six moves. 277 appears as the numerator of the fifth term of the Taylor series for the secant function: : Since no number added to the sum of its digits generates 277, it is a self number. The next prime self number is not reached until 367. Two hundred and seventy-seven is also: * The length of the Grand Canyon in river miles, beginning at Lees Ferry (mile 0) and ending at the Grand Wash Cliffs (mile 277). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「277 (number)」の詳細全文を読む スポンサード リンク
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