Not quite up to Richter's scale

"Gerhard Richter," the gallery wall text at the entrance of this exhibition intones with wince-inducing grandiosity, "is one of the world’s greatest living artists." Perhaps it’s just my jaundiced mind but in the context of this exhibition that sounded like art world code for an excuse: " and that’s why we can get away with filling our entire gallery with just one somewhat boring work of art."

Still, a below-par Gerhard Richter is cleverer than a masterpiece by most other artists. "4900 Colours" consists of 49 pictures, all the same size, each a grid of 100 squares. Each square is one of 25 beautiful colours, a number chosen because it has a mystical significance in Arabian maths.

As you wander around the gallery, you may wonder why the hues go so well together and create such a serene, even euphoric atmosphere. The secret is that they share the same tonal range and they were chosen by the artist to be as "neutral" as possible. Then, the placing of the colours was selected at random by a software programme. They are painted with extreme precision. Each colour is a different lacquered tile, which is glued onto an aluminium backing so that it looks as if it has all been done by a machine. Richter says the idea is to "go beyond the beautiful and the ugly, towards nothing".

The whole of the Serpentine is filled with these techno-zen pictures which are all different and all the same. The work can be assembled any number of different ways. It’s the first ever abstract painting Lego set — originally consisting of 196 panels of 25 x 25 coloured squares (hence the 25 colours).

These simple grids of industrially produced hues were ground-breaking: they overturned 60 years of colour abstraction, from Kandinsky to Rothko, in which artists carefully mixed their hues to reveal spiritual truths and a language of emotions. The charts have proved very influential — Richter’s little rectangles of colour inspired Damien Hirst in his dot paintings.

Now, 40 years later, Richter has updated the charts as brave symbols of the computer age by shifting their organising principle from the pantone catalogues of DIY shops to digital technology. These are the prettiest pixels you will ever see.

Up to this point the symbolism and the art history are pretty satisfying but the logic of the work is just not quite as neat. Richter knows how to spot a good colour but as an exercise in chance this is a bodge-job. The artist picked the colours, a computer generated the combinations, and then a roll of the dice determined the layout of the panels in the gallery. What next? A ouija board to decide the height the work is hung at? The balls in the lottery machine to set the price?

It’s probably the inconsistencies in the concept that makes the work a bit, as the Germans would say, so lala. If you go to this show, you may well enjoy it but unless you practise transcendental meditation on abstract painting, you aren’t going to spend more than 15 minutes here.

Until 16 November (020 7402 6075; www.serpentinegallery.org) Free.

Gerhard Richter: 4900 Colours: Version II
Serpentine Gallery
Kensington Gardens, W2 3XA