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A249724 Numbers n such that on row n of Pascal's triangle there is no multiple of 9 which would be less than any (potential) multiple of 4 on the same row. 5
0, 1, 2, 3, 4, 5, 6, 7, 8, 11, 12, 14, 16, 17, 20, 22, 23, 24, 25, 26, 28, 30, 32, 33, 34, 35, 36, 38, 40, 41, 42, 44, 48, 49, 50, 51, 52, 53, 56, 57, 58, 60, 61, 62, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 76, 77, 78, 80, 84, 86, 88, 89, 92, 94, 96, 97, 98, 100, 101, 102, 104, 105, 106, 107, 108, 110, 112, 113, 114, 115, 116, 120, 121 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Disjoint union of {0} and the following sequences: A048278 (gives 7 other cases where there are neither multiples of 4 nor 9 on row n), A249722 (rows where a multiple of 4 is found before a multiple of 9), A249726 (cases where the least term on row n which is multiple of 4 is also multiple of 9, and vice versa, i.e. such a term a multiple of 36).

If A249717(n) < 3 then n is included among this sequence. This is a sufficient but not necessary condition, e.g. A249717(25) = 5, but 25 is also included in this sequence.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..23590

PROG

(PARI)

A249724list(upto_n) = { my(i=0, n=0, dont_print=0); while(i<upto_n, for(k=0, n\2, if(!(binomial(n, k)%4), i++; write("b249724.txt", i, " ", n); dont_print=1; break, if(!(binomial(n, k)%9), dont_print=1; break))); if(!dont_print, i++; write("b249724.txt", i, " ", n), dont_print=0); n++); } \\ Ugly code.

CROSSREFS

Complement: A249723.

Cf. A007318, A052955, A249441, A249695, A249717, A048278, A048645, A051382, A249722, A249726.

Sequence in context: A173016 A053577 A093515 * A084369 A167211 A067133

Adjacent sequences:  A249721 A249722 A249723 * A249725 A249726 A249727

KEYWORD

nonn

AUTHOR

Antti Karttunen, Nov 04 2014

STATUS

approved

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Last modified May 29 20:42 EDT 2020. Contains 334710 sequences. (Running on oeis4.)