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A096293
Number of iterations of n -> n + (sum of squares of digits of n) needed for the trajectory of n to join the trajectory of A033936.
0
0, 0, 8, 76, 72, 0, 330, 8, 73, 77, 76, 7, 75, 73, 72, 66, 6, 62, 25, 75, 67, 72, 74, 74, 8, 66, 38, 70, 74, 71, 72, 62, 72, 70, 61, 73, 7, 75, 70, 330, 71, 0, 329, 73, 61, 62, 73, 71, 72, 74, 71, 73, 65, 7, 74, 329, 73, 70, 69, 70, 62, 0, 3, 39, 60, 65, 5, 328, 60, 72, 75, 7, 73
OFFSET
1,3
COMMENTS
Conjecture: For any positive integer starting value n, iterations of n -> n + (sum of squares of digits of n) will eventually join A033936 (verified for all n up to 20000).
EXAMPLE
a(3)=8 because the trajectory for 1 (sequence A033936) starts
1->2->6->42->62->102->107->157->232->249->350->384->473...
and the trajectory for 3 starts
3->12->17->67->152->182->251->281->350->384->473...
so the sequence beginning with 3 joins A033936 after 8 steps.
CROSSREFS
Sequence in context: A111685 A302814 A088376 * A355049 A239549 A247828
KEYWORD
base,nonn
AUTHOR
Jason Earls, Jun 24 2004
STATUS
approved