A216386 Number of values of k for which sigma(k)-k is a permutation of decimal digits of k, for 10^(n-1) < k < 10^n.

1, 1, 3, 10, 40, 215, 1224, 6587, 3387628, 50507498

Offset

1,3

Links

Table of n, a(n) for n=1..10.

Formula

a(n) = # { k in A085844 | 10^(n-1) < k < 10^n }. - M. F. Hasler, Feb 24 2014

Example

a(3) = 3 because the values of k satisfying the condition for 10^2 < k < 10^3 are {411, 496, 604}. - V. Raman, Feb 17 2014

Prog

(PARI) a(n)=sum(k=10^(n-1), 10^n, vecsort(digits(k)) == vecsort(digits(sigma(k)-k))) \\ V. Raman, Feb 17 2014, based on edits by M. F. Hasler

Crossrefs

Cf. A085844, A001065.

Sequence in context: A030911 A009374 A297213 * A256157 A137781 A208125

Adjacent sequences: A216383 A216384 A216385 * A216387 A216388 A216389

Keyword

nonn,base,more

Author

V. Raman, Sep 06 2012

Extensions

a(9)-a(10) from Lars Blomberg, Jan 23 2016

Status

approved