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A122205
Number of finite sequences b with b(0) = 1, b(i+1) = b(i)+d where d|b(i), ending with n.
1
1, 1, 1, 2, 2, 5, 5, 12, 17, 31, 31, 96, 96, 197, 324, 629, 629, 1695, 1695, 4374, 6266, 10671, 10671, 34402, 38776, 73274, 109371, 223510, 223510, 634267, 634267, 1527075, 2172013, 3699717, 4557494, 12736034, 12736034, 25473763, 38283071
OFFSET
1,4
FORMULA
a(1) = 1, for n>1, a(n) = sum_{d|n, d<n} a(n-d).
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved