277 (number)

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277 (two hundred [and] seventy-seven) is the natural number following 276 and preceding 278.

276 277 278
Cardinal two hundred seventy-seven
Ordinal 277th
(two hundred seventy-seventh)
Factorization prime
Prime yes
Greek numeral ΣΟΖ´
Roman numeral CCLXXVII, cclxxvii
Binary 1000101012
Ternary 1010213
Senary 11416
Octal 4258
Duodecimal 1B112
Hexadecimal 11516

Mathematical properties

277 is the 59th prime number, and a regular prime. [1] It is the smallest prime p such that the sum of the inverses of the primes up to p is greater than two. [2] Since 59 is itself prime, 277 is a super-prime. [3] 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. [4] It is the largest prime factor of the Euclid number 510511 = 2 × 3 × 5 × 7 × 11 × 13 × 17 + 1. [5]

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. [6] 277 is also a Perrin number, and as such counts the number of maximal independent sets in an icosagon. [7] [8] There are 277 ways to tile a 3 × 8 rectangle with integer-sided squares, [9] and 277 degree-7 monic polynomials with integer coefficients and all roots in the unit disk. [10] On an infinite chessboard, there are 277 squares that a knight can reach from a given starting position in exactly six moves. [11]

277 appears as the numerator of the fifth term of the Taylor series for the secant function: [12]

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. [13]

References

  1. Sloane, N. J. A. (ed.). "SequenceA007703(Regular primes)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  2. Sloane, N. J. A. (ed.). "SequenceA016088(a(n) = smallest prime p such that Sum_{ primes q = 2, ..., p} 1/q exceeds n)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  3. Sloane, N. J. A. (ed.). "SequenceA006450(Primes with prime subscripts)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  4. Fernandez, Neil (1999), An order of primeness, F(p), archived from the original on 2012-07-10, retrieved 2013-09-11.
  5. Sloane, N. J. A. (ed.). "SequenceA002585(Largest prime factor of 1 + (product of first n primes))". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  6. Sloane, N. J. A. (ed.). "SequenceA000124(Central polygonal numbers (the Lazy Caterer's sequence): n(n+1)/2 + 1; or, maximal number of pieces formed when slicing a pancake with n cuts)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  7. Sloane, N. J. A. (ed.). "SequenceA001608(Perrin sequence (or Ondrej Such sequence): a(n) = a(n-2) + a(n-3))". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  8. Füredi, Z. (1987), "The number of maximal independent sets in connected graphs", Journal of Graph Theory, 11 (4): 463–470, doi:10.1002/jgt.3190110403 .
  9. Sloane, N. J. A. (ed.). "SequenceA002478(Bisection of A000930)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  10. Sloane, N. J. A. (ed.). "SequenceA051894(Number of monic polynomials with integer coefficients of degree n with all roots in unit disc)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  11. Sloane, N. J. A. (ed.). "SequenceA118312(Number of squares on infinite chessboard that a knight can reach in n moves from a fixed square)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  12. Sloane, N. J. A. (ed.). "SequenceA046976(Numerators of Taylor series for sec(x) = 1/cos(x))". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.
  13. Sloane, N. J. A. (ed.). "SequenceA006378(Prime self (or Colombian) numbers: primes not expressible as the sum of an integer and its digit sum)". The On-Line Encyclopedia of Integer Sequences . OEIS Foundation.