Laying out 118 tiles…
The 18-column chart is a filing cabinet. Periods 6 and 7 do not actually have a two-element footnote. They have a 32-element row once lanthanides and actinides sit in line. Switch layouts, and the same 118 tiles then tween to new coordinates. They are HTML tiles in a CSS 3D scene, so the symbols stay sharp.
Four maps of the same 118
The classroom table parks f-block underneath. The 32-column form is the period as written: two s columns, fifteen f, nine d, six p. Theodor Benfey’s spiral is a ribbon of atomic number, with the d- and f-blocks as peninsulas. ADOMAH (and Janet’s left-step table before it) sorts by n+ℓ, the Madelung order Aufbau uses. In that map, s-block sits on the right and f-block sits on the left.
Helium’s jump is the argument, animated. 1s² wants to sit with the s-block. A full shell wants to sit with neon. The block map is the filling-order version of the same disagreement.
Questions the morph answers
Which layout is the “real” periodic table?
None of them is more real than the others. The 18-column form is a classroom convenience. The 32-column form is what the periods actually are. Benfey’s spiral and the ADOMAH / Janet left-step table then map other ideas: a continuous atomic-number ribbon, and the n+ℓ filling order.
Why does helium jump when I switch to 32-column?
Helium is 1s², so a filling-order table puts it above neon. The 18-column chart parks it above neon anyway, because a full shell, not the last orbital’s letter, is what makes it a noble gas. The jump is that disagreement, animated.
Is ADOMAH the same as the Aufbau principle?
ADOMAH (and Janet’s left-step table) arranges elements by n+ℓ, which is the Madelung order Aufbau uses. It is not a picture of orbital energies in a many-electron atom. Those energies swap as soon as d and f start to fill. Even so, it is the cleanest quantum-number map of the 118.