prime pyramid

A prime pyramid is a triangular arrangement of numbers in which each row n has the integers from 1 to n but in an order such that the sum of any two consecutive terms in a row is a prime numberMathworldPlanetmath. The first number must be 1, and the last number is usually required to be n, all the numbers in between are in whatever order fulfills the requirement for prime sums. Unlike other triangular arrangements of numbers like Pascal’s triangle or Losanitsch’s triangle, the contents of a given row are not determined by those of the previous row. However, if it happens that one has calculated row n-1 and that 2n-1 is a prime number, one could just copy the previous row and add n at the end. Here is a prime pyramid reckoned that way:


Often row 1 just contains an asterisk or some other non-numerical symbol, but since the idea of adding two numbers in row 1 is moot, here row 1 just contains a 1 per analogy to the following rows and to other triangular arrangements of numbers.


  • 1 R. K. Guy, Unsolved Problems in Number TheoryMathworldPlanetmathPlanetmath New York: Springer-Verlag 2004: C1
Title prime pyramid
Canonical name PrimePyramid
Date of creation 2013-03-22 17:00:03
Last modified on 2013-03-22 17:00:03
Owner PrimeFan (13766)
Last modified by PrimeFan (13766)
Numerical id 4
Author PrimeFan (13766)
Entry type Definition
Classification msc 11A41