```\n         if (D == 0) { //initial deposit\n                   uint256 sumDenoms = 0; \n                        for (uint256 i = 0; i < tkns.length; i++) {\n                              sumDenoms += \n                        AI.getAllowedTokenInfo(tkns[i]).initialDenominator;\n                      }\n                   require(sumDenoms > 0 && sumDenoms <= maxInitialDenominator, \n         "invalid sumDenoms");\n                   deltaN = sumDenoms; //initial numerator and denominator are the \n                same, and are greater than any possible balance in the vault.\n             //this ensures precision in the vault's \n         balances. User Balance = (N*T)/D will have rounding errors always 1 \n         wei or less. \n         } else { \n            // deltaN = (amt * D)/T;\n            deltaN = Arithmetic.overflowResistantFraction(amt, D, T);\n         }\n```\n