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A231718
Positions of ones in A231717.
4
1, 8, 14, 18, 22, 33, 37, 41, 45, 53, 57, 61, 71, 75, 87, 116, 120, 124, 128, 136, 140, 144, 154, 158, 170, 208, 212, 216, 226, 230, 242, 289, 293, 305, 362, 544, 548, 552, 556, 564, 568, 572, 582, 586, 598, 636, 640, 644, 654, 658, 670, 717, 721, 733, 790, 1021
OFFSET
1,2
COMMENTS
This sequence gives all n at which positions the successive terms A219666(n-1) & A219666(n) in the infinite trunk of the factorial beanstalk differ only in one digit position in their factorial base representations (A007623) and the difference of those digits is exactly one.
LINKS
FORMULA
For all n, A230406(a(n)) = A000142(A231719(a(n))).
EXAMPLE
14 is included, because A219666(13) = 40 = '1220' in factorial base representation, while A219666(14) = 46 = '1320' in factorial base, and they differ only by the third least significant digits, and 3-2 = 1.
PROG
(Scheme, with Antti Karttunen's IntSeq-library)
(define A231718 (MATCHING-POS 1 1 (lambda (i) (= 1 (A231717 i)))))
CROSSREFS
Subset of A230422.
Sequence in context: A072835 A367035 A096229 * A212020 A283597 A112277
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 12 2013
STATUS
approved