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”).

A031007
Triangle T(n,k): Write n in base 7, reverse order of digits, to get row n.
18
0, 1, 2, 3, 4, 5, 6, 0, 1, 1, 1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 0, 2, 1, 2, 2, 2, 3, 2, 4, 2, 5, 2, 6, 2, 0, 3, 1, 3, 2, 3, 3, 3, 4, 3, 5, 3, 6, 3, 0, 4, 1, 4, 2, 4, 3, 4, 4, 4, 5, 4, 6, 4, 0, 5, 1, 5, 2, 5, 3, 5, 4, 5, 5, 5, 6, 5, 0, 6, 1, 6, 2, 6, 3, 6, 4, 6, 5, 6, 6, 6
OFFSET
0,3
MATHEMATICA
Flatten[Table[Reverse[IntegerDigits[n, 7]], {n, 0, 50}]] (* Harvey P. Dale, Feb 25 2014 *)
PROG
(PARI) A031007(n, k=-1)={k<0&&error("Flattened sequence not yet implemented."); n\7^k%7} \\ Assuming that columns start with k=0 as in A030308, A030341, ... TO DO: implement flattened sequence, such that A030567(n)=a(n). - M. F. Hasler, Jul 21 2013
CROSSREFS
Cf. A030308, A030341, A030386, A031235, A030567, A031045, A031087, A031298 for the base-2 to base-10 analogs.
Sequence in context: A037849 A037885 A347729 * A010876 A309958 A055400
KEYWORD
nonn,base,tabf,less
EXTENSIONS
Initial 0 and better name by Philippe Deléham, Oct 20 2011
STATUS
approved