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A262903 Numbers that are not leaves but all of whose children are leaves in the tree generated by edge-relation A049820(child) = parent. 5

%I #12 Oct 11 2015 10:54:11

%S 4,5,14,16,32,41,44,77,80,92,101,110,119,128,139,148,158,161,169,176,

%T 191,192,199,215,224,227,234,238,249,262,264,277,296,311,317,327,350,

%U 351,352,360,363,382,385,389,392,395,396,411,427,430,437,448,449,461,464,483,488,518,523,531,532,542,552,561,568,570,577,579,600,601,613,619,632,634,636,645,648,659,665,666,671,682,683,696,705,723

%N Numbers that are not leaves but all of whose children are leaves in the tree generated by edge-relation A049820(child) = parent.

%C Numbers n for which A060990(n) > 0 and A060990(n) = A262900(n).

%C Numbers n for which A262695(n) = 2.

%H Antti Karttunen, <a href="/A262903/b262903.txt">Table of n, a(n) for n = 1..10000</a>

%o (Scheme, with _Antti Karttunen_'s IntSeq-library, two variant definitions)

%o (define A262903 (MATCHING-POS 1 0 (lambda (n) (and (not (zero? (A060990 n))) (= (A060990 n) (A262900 n))))))

%o (define A262903 (MATCHING-POS 1 0 (lambda (n) (= 2 (A262695 n)))))

%Y Cf. A000005, A049820, A060990, A262695, A262900.

%Y Subsequence of A262901 and A236562.

%Y No common terms with A259934.

%Y Cf. also A257512.

%K nonn

%O 1,1

%A _Antti Karttunen_, Oct 06 2015

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Last modified March 28 18:04 EDT 2024. Contains 371254 sequences. (Running on oeis4.)