I setup the installation as specified in the following link 
https://octopus.com/docs/packaging-applications/build-servers/jenkins

The octo pack detects the version number but the Push package doesn't C:\Users\rdair\Desktop\Builtproject\kryptest.${BUILD_NUMBER} .nupkg
failed to match any files

If I set the version manually then everything works fine. Please find log below

[kryptest] $ C:\Octopus\Octo.exe pack --id kryptest --version 1.0.19 --format nuget --basePath C:\Users\rdair\Desktop\Builtproject\ --include . --outFolder C:\Users\rdair\Desktop\Builtproject\output\ --overwrite
Packing kryptest version "1.0.19"...
Saving "kryptest.1.0.19.nupkg" to "C:\Users\rdair\Desktop\Builtproject\output\"...
Done.
INFO: Octo.exe exit code: 0
FATAL: Failed to push the packages: The pattern
C:\Users\rdair\Desktop\Builtproject\kryptest.${BUILD_NUMBER} .nupkg
failed to match any files
Build step 'Octopus Deploy: Push packages' marked build as failure
Finished: FAILURE