A256632 a(n) = the smallest number k such that sigma(k) ends with the same concatenation of digits as n in base 10.

1, 6, 2, 3, 8, 5, 4, 7, 18, 104, 256, 6, 9, 13, 8, 102, 100, 10, 288, 19, 81, 146, 512, 14, 2928200, 68, 64, 12, 1089, 29, 16, 21, 121, 90, 6272, 22, 1600, 37, 18, 27, 441, 20, 722, 43, 1352, 180, 324, 33, 338, 149, 576, 96, 529, 34, 128, 28, 49, 157, 1058, 24

Offset

1,2

Links

Table of n, a(n) for n=1..60.

Example

For n = 5, sigma(8) = 15, which ends in 5. The number 8 is the smallest number with this property so a(5) = 8.

Prog

(Magma) A256632:=func<n|exists(r){k:k in[1..10000000] | (SumOfDivisors(k)-n) mod 10^(#Intseq(n)) eq 0}select r else 0>; [A256632(n):n in[1..100]]
(PARI) a(n)=k=1; d=digits(n); while((sigma(k)-n)%(10^#d), k++); k
vector(50, n, a(n)) \\ Derek Orr, Apr 05 2015

Crossrefs

Cf. A000203, A072566.

Sequence in context: A178054 A195453 A259543 * A201280 A248274 A267568

Adjacent sequences: A256629 A256630 A256631 * A256633 A256634 A256635

Keyword

nonn,base

Author

Jaroslav Krizek, Apr 05 2015

Status

approved