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A306107
Numbers with digits in {0,1,2,3,4} such that every other digit is strictly less than its neighbors.
0
0, 1, 2, 3, 4, 10, 20, 21, 30, 31, 32, 40, 41, 42, 43, 101, 102, 103, 104, 201, 202, 203, 204, 212, 213, 214, 301, 302, 303, 304, 312, 313, 314, 323, 324, 401, 402, 403, 404, 412, 413, 414, 423, 424, 434, 1010, 1020, 1021, 1030, 1031, 1032, 1040, 1041, 1042, 1043, 2010, 2020, 2021, 2030, 2031, 2032, 2040, 2041
OFFSET
1,3
COMMENTS
Terms of A032860 written in base 5.
FORMULA
a(n) = A007091(A032860(n)).
PROG
(PARI) A(Nmax=100, K=4, A=[0..K], i=vector(2*K, i, max(1, i-K+1)), c(T, v)=apply(t->t+T, v))={for(n=0, oo, for(k=10, K*11, if(k%10<k\10, k%10|| i=concat(i, 1+#A))&& A=concat(A, c(k*10^n, A[i[K*n+k%10+1]..i[K*n+K+1]-1])); #A<Nmax||return(A)))}
CROSSREFS
Cf. A306105 .. A306111 and A297147: analog for bases 3..9 and 10.
Cf. A032860 and A032858 .. A032865 for other bases 3..10.
Sequence in context: A108364 A346489 A145028 * A229545 A085932 A214283
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Oct 05 2018
STATUS
approved