A094763 - OEIS

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A094763

Trajectory of 2 under repeated application of the map n -> n + square excess of n.

2, 3, 5, 6, 8, 12, 15, 21, 26, 27, 29, 33, 41, 46, 56, 63, 77, 90, 99, 117, 134, 147, 150, 156, 168, 192, 215, 234, 243, 261, 266, 276, 296, 303, 317, 345, 366, 371, 381, 401, 402, 404, 408, 416, 432, 464, 487, 490, 496, 508, 532, 535, 541, 553, 577, 578, 580, 584, 592, 608

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,1

LINKS

Robert Israel, Table of n, a(n) for n = 0..10000

S. H. Weintraub, An interesting recursion, Amer. Math. Monthly, 111 (No. 6, 2004), 528-530.

MAPLE

a[0]:= 2:

for n from 1 to 100 do a[n]:= f(a[n-1]) od:

seq(a[n], n=0..100); # Robert Israel, Jan 28 2018

PROG

(PARI) lista(nn) = {print1(n=2, ", "); for (k=2, nn, m = 2*n - sqrtint(n)^2; print1(m, ", "); n = m; ); } \\ Michel Marcus, Oct 23 2015