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A162394 Fibonacci numbers (A000045) which are anagrams of Triangular numbers (A000217).

%I A162394 #14 Feb 18 2024 14:49:41
%S A162394 0,1,3,21,55,2584,28657,2178309,5702887,14930352,102334155,267914296,
%T A162394 701408733,2971215073,4807526976,7778742049,12586269025,32951280099,
%U A162394 225851433717,591286729879,1548008755920,10610209857723,27777890035288,72723460248141,308061521170129,498454011879264,806515533049393,1304969544928657,3416454622906707
%N A162394 Fibonacci numbers (A000045) which are anagrams of Triangular numbers (A000217).
%H A162394 Michael S. Branicky, <a href="/A162394/b162394.txt">Table of n, a(n) for n = 1..38</a> (all terms <= 20 digits)
%e A162394 2584 is A000045(18) and is an anagram of 2485 = A000217(70).
%e A162394 28567 is A000045(23) and is an anagram of 67528 = A000217(367).
%o A162394 (Python)
%o A162394 from math import isqrt
%o A162394 from itertools import count, islice
%o A162394 def tris(d): # generator of triangular numbers with d digits
%o A162394     ilb, lb, ub = isqrt(2*10**(d-1))-1, 10**(d-1), 10**d
%o A162394     if d == 1: yield 0
%o A162394     for i in count(ilb):
%o A162394         t = i*(i+1)//2
%o A162394         if t < lb: continue
%o A162394         elif t >= ub: break
%o A162394         yield t
%o A162394 def agen(): # generator of sequence terms
%o A162394     yield 0
%o A162394     f, g, n, adict = 1, 2, 1, dict()
%o A162394     for d in count(1):
%o A162394         T = set("".join(sorted(str(t))) for t in tris(d))
%o A162394         while f < 10**d:
%o A162394             if "".join(sorted(str(f))) in T: yield f
%o A162394             f, g = g, f+g
%o A162394 print(list(islice(agen(), 20))) # _Michael S. Branicky_, Feb 18 2024
%Y A162394 Cf. A000045, A000217.
%K A162394 nonn,base
%O A162394 1,3
%A A162394 _Claudio Meller_, Jul 02 2009
%E A162394 Edited and extended by _Ray Chandler_, Jul 09 2009
%E A162394 a(24)-a(29) from _Chai Wah Wu_, Dec 25 2016