calculates size of redeem script given n pubkeys. Calculation looks like: OP_M (1 byte) + size of each pubkey in redeem script (OP_DATA= 1 byte * N) + pubkey size (33 bytes * N) + OP_N (1 byte) + OP_CHECKMULTISIG (1 byte) => 1 + (1 * N) + (33 * N) + 1 + 1
calculates size of redeem script given n pubkeys. Calculation looks like: OP_M (1 byte) + size of each pubkey in redeem script (OP_DATA= 1 byte * N) + pubkey size (33 bytes * N) + OP_N (1 byte) + OP_CHECKMULTISIG (1 byte) => 1 + (1 * N) + (33 * N) + 1 + 1