Earthworm Sequence/Examples

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Examples of Earthworm Sequence

The earthworm sequence is analysed for all $n \in \set {00, 01, 02, \dotsc, 99}$, not only for the range $\set {10, 11, 12, \dotsc, 99}$.


The first table lists the integers that end up in a loop of $20$ terms:

$n$ $\map h n$ $\map h {\map h n}$ $\map h {\map h {\map h n} }$
$01$, $51$ $02$ $04$ $08$
$27$, $77$ $54$ $08$ $16$
$29$, $79$ $58$ $16$ $32$
$33$, $83$ $66$ $32$ $64$
$41$, $91$ $82$ $64$ $28$
$07$, $57$ $14$ $28$ $56$
$39$, $89$ $78$ $56$ $12$
$03$, $53$ $06$ $12$ $24$
$31$, $81$ $62$ $24$ $48$
$37$, $87$ $74$ $48$ $96$
$49$, $99$ $98$ $96$ $92$
$23$, $73$ $46$ $92$ $84$
$21$, $71$ $42$ $84$ $68$
$17$, $67$ $34$ $68$ $36$
$09$, $59$ $18$ $36$ $72$
$43$, $93$ $86$ $72$ $44$
$11$, $61$ $22$ $44$ $88$
$47$, $97$ $94$ $88$ $76$
$19$, $69$ $38$ $76$ $52$
$13$, $63$ $26$ $52$ $04$


The second table lists the integers that end up in a loop of $4$ terms:

$n$ $\map h n$ $\map h {\map h n}$ $\map h {\map h {\map h n} }$
$05$, $55$ $10$ $20$ $40$
$35$, $85$ $70$ $40$ $80$
$45$, $95$ $90$ $80$ $60$
$15$, $65$ $30$ $60$ $20$


The second table lists the integers that end up in a loop of $1$ term, that is, the degenerate case that ends in $0$:

$25$, $75$ $50$ $00$ $00$