A323635 Lexicographically earliest sequence of distinct positive integers such that the nested square root sqrt(a(n) + sqrt(a(n-1) + ... + sqrt(a(1))...)) is an integer.
1, 3, 2, 7, 6, 13, 5, 22, 4, 33, 10, 12, 21, 11, 32, 19, 20, 31, 30, 43, 9, 45, 18, 44, 29, 58, 8, 60, 17, 59, 28, 75, 16, 76, 27, 94, 15, 95, 26, 115, 14, 116, 25, 138, 24, 163, 23, 190, 35, 42, 57, 41, 74, 40, 93, 39, 114, 38, 137, 37, 162, 36, 189, 50, 56, 73, 55, 92, 54, 113, 53, 136
Offset: 1
Links
- Ivan Neretin, Table of n, a(n) for n = 1..10000
- Mathematics Stack Exchange, a_n is the smallest positive integer number such that ...
Programs
-
PARI
lista(nn) = {my(va = vector(nn), lastsq); va[1] = 1; lastsq = 1; for (n=2, nn, my(k = ceil(sqrt(sqrtint(lastsq)))); while (#select(x->(x==(k^2-sqrtint(lastsq))), va), k++); va[n] = k^2-sqrtint(lastsq); lastsq = k^2;); va;} \\ Michel Marcus, Oct 13 2020
Comments