login
A257512
Those vertices of the binary beanstalk whose children are both leaves.
5
10, 18, 25, 34, 41, 54, 56, 66, 73, 86, 88, 102, 110, 117, 119, 130, 137, 150, 152, 166, 174, 181, 183, 198, 206, 213, 222, 229, 243, 244, 246, 258, 265, 278, 280, 294, 302, 309, 311, 326, 334, 341, 350, 357, 371, 372, 374, 390, 398, 405, 414, 421, 435, 436, 446, 453, 467, 468, 483, 491, 498, 499, 501, 514
OFFSET
1,1
COMMENTS
Numbers n for which both A079559(A213723(n)) and A079559(A213724(n)) are zero.
Numbers which occur twice in A257507.
EXAMPLE
10 is present, because A011371(12) = A011371(13) = 10, and both 12 and 13 are terms of A055938. See also Paul Tek's illustration.
PROG
(Scheme, with Antti Karttunen's IntSeq-library)
(define A257512 (MATCHING-POS 1 0 (lambda (n) (and (zero? (A079559 (A213723 n))) (zero? (A079559 (A213724 n)))))))
CROSSREFS
First differences: A256490.
Subsequence of A005187, A213717 and A257508.
Sequence in context: A333999 A245578 A165250 * A125689 A244573 A230356
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 03 2015
STATUS
approved