A red sideband has a real floor at packet zero; a blue sideband has no matching ceiling in this model. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Red sideband has a real floor at packet zero
Chapter two already established that a red sideband at packet index zero is rejected -- there is no packet below zero to drop into, so the accepted bit reads 0.
ni=0,nf=0,a=0
Blue sidebands never hit an equivalent ceiling in this model
One packet above the floor, red is accepted normally. Chapter five's blue-growth scan only ever checked small starting packets, up through two. Scanning a blue sideband from a much higher starting packet shows this toy model enforces a floor for red but never enforces any matching ceiling for blue.
kindredredblueni0120nf0021a011
A high-packet blue sideband is still accepted without limit
Starting from packet 20, the blue sideband still adds one packet and is still accepted. Nothing in this model's blue-sideband rule checks for an upper packet limit the way the red rule checks for the zero floor.