# This b-file was computed by Antti Karttunen, 2021-03-29 # in GP/PARI CALCULATOR Version 2.9.4 (released) amd64 running linux (x86-64/GMP-6.1.2 kernel) 64-bit version, compiled: Dec 19 2017, gcc version 7.3.0 (Ubuntu 7.3.0-1ubuntu1), threading engine: pthread # with the following program: # # A104513(n) = if(!bitand(n,n-1), 0, my(d); for(k=0,n-2,forstep(j=min(n,k+1+sqrtint(2*n)),k+2,-1, d = binomial(j+1,2) - binomial(k+1,2); if(d==n,return(j-k),if(d