login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A121578
Values m of number pairs (m,n) which yield associated matching times on the clock with interchanged hour and minute hands for corresponding n in A121577.
1
0, 12, 24, 36, 48, 60, 72, 84, 96, 108, 120, 132, 1, 13, 25, 37, 49, 61, 73, 85, 97, 109, 121, 133, 2, 14, 26, 38, 50, 62, 74, 86, 98, 110, 122, 134, 3, 15, 27, 39, 51, 63, 75, 87, 99, 111, 123, 135, 4, 16, 28, 40, 52, 64, 76, 88, 100, 112, 124, 136, 5, 17, 29, 41, 53, 65
OFFSET
1,2
COMMENTS
The pair (m,n) is reflexive, i.e., when n=m, m=n.
In fact, for n = 12*i + j, with 0 <= i < 12; 0 <= j < 12, m = i + 12*j. - Lekraj Beedassy, Aug 09 2006
REFERENCES
A. P. Domoryad, Mathematical Games and Pastimes, Problem 15 pp. 242;289 Pergamon Press NY 1965.
Y. Perelman, Mathematics can be fun, pp. 236-8 Mir Moscow.
CROSSREFS
Cf. A121577.
Sequence in context: A094529 A270571 A044852 * A044897 A008594 A033024
KEYWORD
fini,nonn
AUTHOR
Lekraj Beedassy, Aug 08 2006
STATUS
approved