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A227793 Numbers whose digital sum is a multiple of 5. 4
0, 5, 14, 19, 23, 28, 32, 37, 41, 46, 50, 55, 64, 69, 73, 78, 82, 87, 91, 96, 104, 109, 113, 118, 122, 127, 131, 136, 140, 145, 154, 159, 163, 168, 172, 177, 181, 186, 190, 195, 203, 208, 212, 217, 221, 226, 230, 235, 244, 249, 253, 258, 262, 267, 271, 276 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Most first differences are 5, 9 and 4. First differences are strictly less than 10. First occurrences d of first difference a(i+1) - a(i) are for (d, i, a(i)) in {(5,1,0), (9,2,5), (4,4,19), (8,20,96), (3,60,299), (7,100, 997), (2,800,3999), (6, 2000, 9998), (1,10000,49999)}. - William Hitt, Apr 21 2014; comments modified by David A. Corneth, Jun 08 2016

a(10000) = 49999 is the smallest term that is congruent to 4 modulo 9. - Bruno Berselli, Feb 09 2016

LINKS

Table of n, a(n) for n=1..56.

MATHEMATICA

Select[Range[0, 280], IntegerQ[Total[IntegerDigits[#]]/5] &] (* Bruno Berselli, Feb 09 2016 *)

PROG

(PARI) isok(n) = {if (n == 0, return (1)); digs = digits(n); return (sum(i=1, #digs, digs[i]) % 5 == 0); } \\ Michel Marcus, Sep 23 2013

(PARI) a(n) = n--; m=10*(n\2); s=sumdigits(m); m+(4-(s-1)%5)+5*(n%2==1) \\ David A. Corneth, Jun 05 2016

(MAGMA) [n: n in [0..300] | IsZero(&+Intseq(n) mod 5)]; // Bruno Berselli, Sep 23 2013

(MAGMA) [n: n in [0..300] | IsIntegral(&+Intseq(n)/5)];  // Bruno Berselli, Feb 09 2016

CROSSREFS

Cf. A007953.

Subsequences: A052219, A052224.

Sequence in context: A102884 A071852 A275809 * A022139 A277351 A143707

Adjacent sequences:  A227790 A227791 A227792 * A227794 A227795 A227796

KEYWORD

nonn,base

AUTHOR

Michel Marcus, Sep 23 2013

STATUS

approved

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Last modified October 18 00:20 EDT 2019. Contains 328135 sequences. (Running on oeis4.)