A306107 Numbers with digits in {0,1,2,3,4} such that every other digit is strictly less than its neighbors.

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.

Links

Table of n, a(n) for n=1..63.

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

Adjacent sequences: A306104 A306105 A306106 * A306108 A306109 A306110

Keyword

nonn,base

Author

M. F. Hasler, Oct 05 2018

Status

approved