#!/bin/bash
POWER_SET="{{} {1} {2} {3} {4} {1,2} {1,3} {1,4} {2,3} {2,4} {3,4} {1,2,3} {1,2,4} {1,3,4} {2,3,4} {1,2,3,4}}"
SUBSETS="1 2 3 4"
for element in $POWER_SET; do
  for sub in $SUBSETS; do
    if [[ $element == *$sub* ]]; then
      echo "element containing $sub: $element"
    fi
  done
done