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A321536 Write n in base 10, lengthen all the runs of successive identical digits by 1. 3
0, 11, 22, 33, 44, 55, 66, 77, 88, 99, 1100, 111, 1122, 1133, 1144, 1155, 1166, 1177, 1188, 1199, 2200, 2211, 222, 2233, 2244, 2255, 2266, 2277, 2288, 2299, 3300, 3311, 3322, 333, 3344, 3355, 3366, 3377, 3388, 3399, 4400, 4411, 4422, 4433, 444, 4455, 4466 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

A321537(a(n)) = n. Compare A321538.

LINKS

Giovanni Resta, Table of n, a(n) for n = 0..10000

EXAMPLE

10 -> 1100, so a(10)=1100; 11->111, so a(11)=111.

MATHEMATICA

a[n_] := FromDigits@ Flatten[ Append[ #, Last@#] & /@ Split@ IntegerDigits[ n]]; a /@ Range[0, 46] (* Giovanni Resta, Nov 13 2018 *)

PROG

(Python)

from re import split

def A321536(n):

    return int(''.join(d+d[0] for d in split('(0+)|(1+)|(2+)|(3+)|(4+)|(5+)|(6+)|(7+)|(8+)|(9+)', str(n)) if d != '' and d != None)) # Chai Wah Wu, Nov 13 2018

(PARI) a(n)={my(v=digits(n)); my(L=List()); for(i=1, #v, my(t=v[i]); if(i==1 || t<>v[i-1], listput(L, t)); listput(L, t)); fromdigits(Vec(L))} \\ Andrew Howroyd, Nov 13 2018

CROSSREFS

A base-10 analog of A175046.

Cf. A321537, A321538.

Sequence in context: A280826 A020338 A052191 * A110732 A044836 A338754

Adjacent sequences:  A321533 A321534 A321535 * A321537 A321538 A321539

KEYWORD

nonn,base,easy

AUTHOR

N. J. A. Sloane, Nov 13 2018

EXTENSIONS

More terms from Giovanni Resta, Nov 13 2018

STATUS

approved

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Last modified September 28 18:04 EDT 2021. Contains 347716 sequences. (Running on oeis4.)