Cryptic crossword No 3,791

Across

1. See 24dn
2. Appearing in top right corner of periodic table around nitrogen, unrelated to 2 (9)
3. Elder fit, as regularly crosses from Southpaw? (5)
4. Right gene reversed by operating system, beginning to culminate in big apple he created... Lucky 13, 28 and 3! (4,8)
5. Remarkably, bus fills with great joy (8)
6. Expensive brew! (5)
7. Works too hard (as a hack), with slip in video's editing (9)
8. Indications of lazy slacker (my son) returning (7)
9. Spiteful desire to accommodate snake (7)
10. See 19ac
11. Country boy, he's madly pursuing sex (10)
12. In Italy you get a kiss with these flowers (6)
13. Warrior in graphic account, little blossom taking on nine from Rome (7)
14. Joins up sad loners, including student (7)
15. Gospel is too cool to be hot! (4)
16. Lots of words from Dutch East India company ably winning over union, and later a king (10)

Down

1. A lot to learn from submarine partner's reversal (8)
2. Enchant with tight turnaround in a fine arrangement (9)
3. As 24 13 famously said when kicking North out (roughly) "I wholly blame investors!" (7,4 7 2) (7,13)
4. Kindles start of trust, taking one in and being most generous (9)
5. Prey flap about, but caught by this, many can no longer take to the wing (8)
6. Hit is thanks for one 24 12 opposed (7)
7. Joins up using molten tin less (7)
8. Lender more certain to pursue defaulter's very heart? (6)
9. Leader Florida sect maligned? (5,6)
10. Encourage with this type of cable (4)
11. See 8dn
12. See 8dn
13. Country girl seen playing up earlier (7)
14. Looks after half of children on dubious vacation (5)
15. Fantastically strong fighter with great prize to win losing head taking on nine from Rome (6)
16. Presided in court on date this material became scarce in the 18th century (9)