4K Output via HDMI on MBP 2015

Macbook Pro 13" early 2015 using HDMI cable into 4K TV will not display or give 4K option in Display Preference pane. Only 1080p, 1080i, 720p, 1600 x 900. Display is Seiki SE39UY04 that only displays 4K at 30Hz. Only refresh rate given in pull down are 60Hz, NTSC, 50Hz PAL, 24Hz. Tried all without change in resolution options.

Cable was used on standard HD setup. Are there special 4K cables maybe? Advice please.