AZPC created the Oddly Triangular contest on 9/7/22. The challenge is to find the longest sequence of N odd digits such that sum(1:value) is composed of only odd digits. The contest ended on 9/8/22 as Rokicki created a 3.6 million digit solution with the implication that an infinite length pattern had been determined. [N=2, 17, sum(1:17)=153]
Part 5 is a generalization of multiple solutions to find Rokicki's result.
Reviewing the N=8/11/14 3/7/9 solutions determine a form such that N=5+3*n.
The values 397979797973 and 399799799799799733 has N=6+6*n given the generalization of 3[1]9[n]7[1]9[n]7[1]9[n]7[1]9[n]7[1]9[n]7[1]3[n]
Usage of matlab java math can be seen in the Test Suite. A function zcombvec is given in the function template to facilitate creation of all vectors that only use the 3/7/9 digits. Usage of zcombvec is not required.
M=OddlyTri5p3n_379(N) where N=digit length, M is a string of length N.
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Last Solution submitted on Sep 28, 2022

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Tim William David Hill Ramon Villamangca

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