BJs has 36-Count Charmin Ultra Soft Toilet Paper (198 sheets per roll) for $19.99.
There is a P&G Buy 3 items and get a $20 award offer going on thru November 1 at BJs. $20 will be loaded to your Primary Membership on 11-8-17 to be used from 11-8 to 11-22-17 at BJs. The P&G Buy 3, Earn a $20 Award terms state that Charmin Ultra Soft 30-36 rolls qualify for this offer. Limit 1 award per Primary Membership. Instore only. Award cannot be redeemed online.
198 2 ply sheets per roll.
36 rolls x 3 packs x 198 sheets=21384 sheets
$40 / 21384 sheets= $0.00187 per sheet (after accounting for $20 award)
My BJs has the Charmin Ultra Soft Toilet Paper (36=100 reg rolls) for $19.99. YMMV as different stores may have different prices and may not have this particular size. You can check online to see if your store carries this item at this price.
I haven't tried this offer out yet. If this offer doesn't activate the $20 award, I plan to just return the toilet tissue.